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By C. L. Colburn

THE statutory requirements of the States and the district rules are, broadly speaking, similar. There is just enough difference to make it tantalizing. DIFFERENCES IN STATE LEGISLATION GOVERNING THE LOCATION OF MINING CLAIMS Discovery Discovery is the first step in the location of the claim. The provision of the Revised Statutes (2320) is, "No location of a mining claim shall be made until the discovery of the vein or lode within the limits of the claim located." Strictly speaking, discovery may be defined as the finding of ore or metalliferous rock in place in a well-defined vein. This definition was too strict, so discovery extended later to cover such indications of the presence of ore, within rock in place, as would justify an experienced miner in spending his time and money with a reasonable expectation of finding ore in paying quantities. According to Colorado statutes a discovery must show a well-defined crevice; in Arizona, a lode, deposit, or mineral in place; in Montana, a well-defined crevice or valuable deposit; in Nevada, a lode or deposit of mineral in place. It is wrong to require a discovery. An honest prospector, wishing to obey the law, finds himself compelled, in most cases, to evade this point. In Clear Creek district, Colorado, a quartz seam will constitute a discovery; in Butte, a red capping; in Leadville or Ely, it is any place where a man can find a piece of vacant ground big enough upon which to sink a 10-ft. hole. If the vein or deposit outcrops a man can show a discovery, but if it does not outcrop it is foolish to compel him to show one; and this point has been gently side-stepped. Any hole 10 ft. deep now constitutes a discovery. It is no use having laws that the people cannot consistently obey. No sane man will dig unless he expects to find mineral, and he should be protected while digging. He should be required to show that he has mineral ground only when he comes to patent.

Jan 6, 1914

By H. J. Levinstein, W. H. Robinson

A method of chemically polishing silver for metal-lographic examination has been developed. The samples are prepared by polishing on 0, 2/0, and 3/0 paper. They are then polished on 600 micro-cut paper, followed by a final mechanical polish on a cloth containing 5µ diamond paste. The samples are then chemically polished in a solution of 100 cc of saturated chromic acid and 5 cc of a 5 pct HC1 solution. The chemical polishing is performed by swabbing with a cotton ball saturated with the solution. During the chemical polishing, the sample is rinsed frequently in running water. Polishing in this manner for 5 min is sufficient to remove the strained material from the previous polishing operations. The amount of material removed is approximately 4µ/min. The surface obtained is flat and free of pits. Fig. 1 is an interference micrograph of a silver surface polished by this technique. If the solution employed is of improper HC1 content, an interference color film will form on the sample. This film can be removed either by swabbing with a cotton ball saturated with ortho-

Jan 1, 1962

J. E. JOHNSON, JR., New York.-It seems to me that it ought to be somebody's job to tie these notch tests with the reversed-stress tests, because the thing that causes failures in structures, in a great majority of cases, is where the material is stressed repeatedly up somewhere near the elastic limit, and the repetition of that stress seems to bring about what I suppose you may call a growth of crystals and that eventually develops into a break. It seems to me that it would be of the greatest value if there could be a coordination of the results of a shock test of some kind with the reversed-stress test, so that we could be sure that a material that had shock-test resistance would have reversed-stress resistance. H. F. MOORE,* Urbana, Ill.-The question raised by the speaker concerning the correlation of results from impact tests of notched bars with the results of repeated-stress tests is a very complicated one. Impact on a specimen sends energy into the specimen, and if the specimen absorbs this energy without fracturing there must be developed both stress and elongation. A notch in the specimen allows but little elongation to take place before rupture, and develops the ductility of the

Jan 5, 1919

News has just been received that Flight Commander William T. Hall, a Junior Member of-the Institute, was killed in action on Saturday, May 19, 1917. According to the' Toronto Star, Commander Hall was 24 years of age, a native of Toronto, and a grandson of the late William Kersteman. During the four years of his course in mining at the School of Practical Science, Toronto University, he passed every examination with honors. When war was first declared Commander Hall endeavored to join the artillery as an officer, and for that purpose secured a provisional lieu- tenancy with a Hamilton battery, but he did not receive an overseas appointment, and on being graduated as a mining engineer in 1915, he was offered a position in Chile, which he accepted. He left Toronto on May 27, 1915, and was engaged in Chile as a mining engineer for nearly a year. In the latter part of April, 1916, he decided to offer himself again for service at the front. He crossed the Andes and sailed for Liverpool, where he landed on May 13, 1916. On May 27, 1916, Capt. Hall was given a commission as lieutenant in the Royal Flying Corps. He went to the front on Sept. 1, 1916, and remained there continuously. On April 4, 1917, he was promoted from lieutenant to the rank of flight commander. No details of how Commander Hall came by his death have as yet been received.

Jan 1, 1918

By D. Malhotra, R. M. Hoover, F. N. Bender

The paper discusses the effect of aeration and agitation on grade and recovery of molybdenite. A series of factorially designed flotation tests were carried out in a "Leeds Automatic Laboratory Flotation Cell." Analysts of flotation results indicate that molybdenite has fast floating and slow floating components. The rates of fast floating components, which do not create a problem inflotation, could be varied by changing agitation or airflow rates. However, the rate of slow floating components was stable and was only a function of residence time. Aeration has a significant effect on the grade of MoS2 and only a slight effect on the recovery of MoS2. Agitation has a slight effect on the grade, but does not effect the recovery of molybdenite. The implications of the results on the design of flotation cells and control and optimization of the existing circuits are also considered.

Jan 1, 1981

By J. C. Kerkering, J. C. Franklin, T. O. Meyer, R. W. McKibbin

A continuous survey of radon gas was made in two interconnecting stopes in a southwestern U. S. uranium mine to determine how the various phases of the mining cycle affected the radon concentration. The radon was monitored continuously with five detectors. One detector monitored the intake air, one the exhaust air, and three the stope air. The radon concentrations present during slushing, blasting, and exhaust fan shutoff were compared with concentrations on a nonwork day as a base level. Inside the stope, the radon concentration increased about 40% during slushing and 425% after blasting. Intake air radon increased 1600% and the stope air increased 550% while the surface exhaust fan was off.

Jan 1, 1979

THIS method of melting with a little wind furnace is called by many melting with air. It is a method that is done with little labor. First a furnace is made with crucibles and charcoal. It is small or large as you wish, without blast from bellows, but not without a draft of air which proceeds from the place where it is made and from the arrangement of the furnace.* This, after a certain period of time, has the effect of melt- [ ] gin the thing in the quantity that you wish, provided, however, that you proportion it properly to the space, to the fire, and to the air which makes the wind. In order to make this, the aforesaid furnace is first made of bricks, or it is dug out of an elevation of stone or [106V] in a wall of clay. It can also be made portable with iron bars and loam as I shall tell you. However you may make it, you must place it in a spot that is windy, for instance, in some large room or opposite doors or windows. It is made round or square as is most pleasing to him who is to make it. But here we will now say that it is to be made square for greater convenience of building with bricks. Having chosen the place, make it a half

Jan 1, 1942

By W. F. Laverty

Two recent papers in this journal1,2 contain experimental evidence for an anomaly in the concentration gradient for tracer diffusion. In both papers, the authors suggest that this anomaly is due to a Gibbs' absorption effect. Their hypothesis is that surface active tracer elements tend to remain in or near the surface adsorption layer, thereby altering the diffusion flux and concentration gradient. It is not clear how the anomaly can be explained in terms of an adsorption effect. Surface tension forces act parallel rather than perpendicular to a surface and therefore should affect only the rate of spreading of surface active agents tangentially across a surface. Frenkel3 has given a short treatment of surface tension as a driving force for surface diffusion. While the equilibrium concentration of a surface active agent at the surface of a solution is known to be higher than in the bulk, its chemical potential is necessarily the same. It is difficult to see how adsorption can result in an anomaly in the chemical potential gradient, which is the driving force for diffusion. A more detailed explanation by the authors of the adsorption mechanism is in order. A similar anomaly does not seem to arise where

Jan 1, 1970

By Magnus Troilius

The method of using the bromine process of determining sulphur in steel, described below, is in successful use at the Midvale Steel Works. Ten grams of drillings are weighed out and put into the 1/2-liter flask A, with long neck. The flask is connected with a wide glass tube C', which, in its turn, is connected with the absorption bulbs B, containing HCI, 1.12 specific gravity, and ahout 5 C.C. of bromine. The wide tnbe C causes the vapor to condense and flow back into the flask A during boiling. The bulbs B connect with a long glass tnbe, which may be made to carry off the bromine fumes through a hole in a window, or, better still, through a flue with powerful draught. The connections being made, 100 C.C. of boiling water are run in through the thistle tube T. The air is thus completely driven out of the flask. 100 C.C. of HC1 (about 1.19 specific gravity) are then run in. When the gas begins to run rattler slowly through B, heat is applied until boiling gradually ensues. The steel being completely dissolved, the apparatus is disconnected, and the contents of B rinsed out into a beaker of 100 C.C. capacity, into which a few C.C. of a concentrated solution of BaCI, have been previously introduced. Heat is then applied (best by means of the hot iron plate) until the bromine is completely driven off and the BaSO, has settled nicely to the bottom. The BaSO4, is then filtered off on a small

Jan 1, 1884

First Session BRASS Wednesday, A.M., Nov. 29 Co-Chairmen: CARTER S. COLE, Staff Engineer, A.S.T.M. E. A. ANDERSON, Chief of Metals Section, Research Div., New Jersey Zinc Co. (of Pa.) Second Session BRASS Wednesday, P.M., Nov. 29 Co-Chairmen: D. K. CRAMPTON, Director of Research, Chase Brass and Copper Co., Inc. A. W. TRACY, Metallurgist, The American Brass Co. Dinner and Technical Session Wednesday Evening, Nov. 29 Toastmaster: N. L. MOCHEL, Manager Metallurgical Engineering, Westinghouse Electric Corp. Talk on "How Do Things Look Today and For the Future" RALPH KELLY, President, Baldwin Locomotive Works Technical Paper on Stress-Corrosion Cracking E. H. Dix, JR., Assistant Director of Research and Chief Metallurgist, Aluminum Company of America Third Session BRASS Thursday, A.M., Nov. 30 Co-Chairmen: W. B. PRICE, Director of Research, Scovill Manufacturing Co. A. L. JAMIESON, Associate Metallurgist, Frankford Arsenal First Session LIGHT METALS Thursday, P.M., Nov. 30 Co-Chairmen: L. L. WYMAN, Metallurgist, General Electric Co. M. A. HUNTER, Professor of Metallurgical Engineering and Head, Dept. of Metallurgical Engineering, Rensselaer Polytechnic Institute Second Session LIGHT METALS Thursday Evening, Nov. 30 Co-Chairmen: R. T. WOOD, Chief Metallurgist, American Magnesium Corp. J. D. HANAWALT, Director, Metallurgical Dept., Dow Chemical Co. First Session STEEL Friday A.M., Dec. I Co-Chairmen: H. S. RAWDON, Chief, Division of Metallurgy, National Bureau of Standards A. L. FEILD, Director of Research, Rustless Iron and Steel Corp. First Session MISCELLANEOUS METALS Friday P.M., Dec. I Co-Chairmen: E. A. ANDERSON, Chief of Metals Section, Research Div., New Jersey Zinc Co. (of Pa.) CARTER S. COLE, Staff Engineer, A.S.T.M.

Jan 1, 1945

By W. C. Kerr

ThE distribution of gold is obviously much wider than is Commanly supposed. Resides the usual matrices, vehicles, or associates, such as quartz, pyrite, chalcopyrite, etc., I find it occurring in quite a range of common rocks. For example, at the Rhodes mine, in Gaston County, a body of 9 to 12 feet of decoroposed, light-gray gneiss was worked together with the strings of quartz, and yielded from six to ten dollars to the ton. A mine in Moore County yields its gold mainly from a feldspathic schist. In the famous King's Mountain mine, in Gaston County, the gold is obtained not only from the seams of quartz in a blue, hydromicaceous schist, but a 60-foot ledge of grayish-blue, fine-grained, schistose limestone is quarried out bodily and sent to the stamps. It is gold-bearing throughout. In Montgomery County the singular concretionary, conglomeritic, quartzite schist, which contains Emmons's palceotrochis, is gold-bearing over wide tracts of country. This fact was noticed by Dr. Emmons. But a still more striking and significant fact is, that a large part of the gold of Montgomery, Davidson, and Randolph counties,

Jan 1, 1882

(The following list contains the names of those members of the Institute of whose connection with military service we have only recently become acquainted; it also includes the names of a few who have recently been promoted or transferred, indicated by a *. A complete list was published in the Year Book, issued as a supplement of the Bulletin for March, 1918.) ALLEN, Roy H., Capt., Air Service, Bureau of Aircraft Production, Washington, D. C. *AMIDON, CLAUDE E., Chemical Warfare Section', Astoria, L. I. *ARCHBALD, HUGH, 311th Infantry, 78th Division, American E. F. ASKIN, THOMAS B. H., Radio Station, Cavite, P. I. *AYER, FRANK A., Lieut., Commanding Officer, -270th Aero Squadron, American E. F. BARBA, W. P., Lieut. Colonel, Ordnance, U. S. A., Washington, D. C. *BARRETT, LESLIE P., 1st Lieut., 5th Field Artillery, American E. F. BLICKENSDERFER, F. C., 1st Lieut., N. A., Ordnance Dept., Edgewood Arsenal, Edgewood, Md. *BROOKS, FLOYD R.., Lieut., Canadian Engineers, Seaford, England. BROWN, GEORGE M., Co. G, 1st Replacement Regiment, Washington Barracks, D. C. *BRUNEL, LOUIS J., Lieut., 5th Field Artillery, Brigade Headquarters, American E. F. *BRUNTON, D. W., Cons. Engr., Naval Consulting Board, Washington, D. C.

Jan 11, 1918

By E. T. Cox

WHILE engaged, in the year 1856, in determining the oil-bearing properties of some bituminous coals from Western Kentucky, by subjecting them to dry distillation in an iron retort, which held about a pint, and to the neck of which were attached several bottles, for collecting the carbon oils, and washing and measuring the gas, I observed .that there was a very great gain in the weight of coke thus made, over that obtained from the same coal when charred in a platinum crucible, as is usual in the laboratory for making the proximate analysis of coal. It was thought at the time that the increase of coke, by the former mode of treating the coal, was due to the pressure which the retarded gas exerted upon the solid carbon, and the possible fixing of a portion of the carbon from the volatile hydrocarbons. For the purpose of obtaining a more definite idea of the effects of pressure on the coking of coals, a series of experiments were made this spring under my direction, by my assistant, Dr. G. M. Levete. The results are highly instructive and full of interest, since they point out some peculiarities in the nature of bituminous coals which

Jan 1, 1875

Starting in 1940, national prize-paper contests for Student Associates and members of Student Chapters of the Institute have been conducted by a Sub- committee of the Committee on Student Relations Five cash prizes of $100 each may be given annually To be eligible for the national contest, a paper must have been the prize winner in a preliminary contest conducted by a Local Section of the Institute The money for the national prizes is drawn from the corpus of a special fund begun in 1940 by a contribution of $2,500 made by D C Jackling, and to which others have made substantial contributions since that time Contributions to the fund from members who are interested will be welcome since the original contributions are about exhausted A special committee, headed by Donald H McLaughlin, was appointed in 1952 to obtain further funds

Jan 1, 1952

By S. F. Shaw

Fox some time it has been more or less recognized within the industry that a scientific control of flowing wells would result in increased production and a greater ultimate recovery of oil. About two years ago it was proposed by the writer that this control should follow principles worked out by him while handling large air-life operations. In the case of wells that had ceased to flow where a large quantity of liquid was present, the use of these principles would result in a large increase of production by using compressed air or gas to flow the well; in the case of a well flowing naturally it would take the form of controlling the gas associated with the oil, resulting either in immediate increase of production or in a reduction of the gas consumed per barrel of oil, and in both cases would result in a greater ultimate recovery from the sand. The Roxana Petroleum Corp., appreciating the advantages to be obtained by a scientific application of the principles of the air lift to oil wells, recently engaged, for a limited time, the services of the writer to work out some of the problems involved. The work was carried out at Braman, Garber and Tonkawa in Oklahoma, and at Oxford in Kansas. Following some suggestions of the writer a well was also equipped by the Roxana company at Smackover by A. S. Field.

Jan 11, 1926

By Ernest N. Patty

Placer gold-bearing gravels of interior Alaska and the Yukon are, for the most part, permanently frozen, and are described as permafrost. The first step in preparing these gravels for dredging is to strip by bulldozer the surface layer of tundra, brush, and scrub timber, and to expose the ebony colored surface of the frozen mud at the grass roots. This mud varies from a frozen, muddy ooze to a sandy silt and locally may contain layers of peat. The whole mass is intercalated with ice dikes and lenses. The thickness will vary from a few feet up to 100 ft, depending upon local conditions. A freshly exposed surface will thaw to a depth of 4 in. per day during the summer season. Common practice is to expose a large surface of this mud to the sun and each day's thaw is then swept off by water and carried away in suspension.

Jan 1, 1951

By G. A. Alers, F. Borik

Rolled sheet products are elastically anisotropic and a large number of measurements of Young's modulus and rigidity modulus are necessary to completely specify their elastic properties. This paper describes and uses a simple measurement technique to obtain the nine elements of the elastic modulus tensor from which all the elastic The elastic properties of a polycrystalline material are usually specified by giving the Young's modulus E and the rigidity modulus G. Unfortunately, these two moduli by themselves are insufficient to completely specify the elastic properties because the rolling process introduces a preferred orientation which makes the material properties can be deduced. In particular, the variation of Young's modulus and the rigidity modulus in the principal planes of a sheet of ausformed steel were deduced. Furthermore, the variation of Young's modulus in the rolling plane was compared with direct measurements. anisotropic. This anisotropy makes E and G functions of the orientation of the test specimen in the sheet so that a complete description of the elasticity requires many measurements on a large number of specimens. A more fundamental approach to the problem is to consider the sheet as a single crystal and measure the elements of its elastic modulus tensor. Although this appears formidable, there have been developed recently high-frequency ultrasonic techniques which yield these tensor elements directly. The symmetry of a rolled sheet is such that it behaves elastically as if it were an orthorhombic

Jan 1, 1965

Discussion of the paper of HOWLAND BANCROFT, presented at the Salt Lake meeting, August, 1914, and printed in Bulletin No. 91, July, 1914, pp. 1767 to 1769. THEODORE SIMONS, Butte, Mont. (communication to the Secretary*). -While preparing maps and models for use in mining litigations the writer was frequently confronted with the problem referred to in Mr. Bancroft's paper. His chart gives the apparent angle of dip with which a vein should be plotted on a vertical section not at right angles to the strike of the vein. For a quick determination of this apparent angle the writer has used an exceedingly simple graphical method, which he believes may prove helpful to engineers engaged in practical work. It is submitted, not as a criticism of Mr. Bancroft's paper, but as a means of solving the same problem when no chart is available and when calculations would consume too much time. The writer's method requires merely a few lines marked off on a piece of tracing cloth, as shown in Fig. 1: Draw line be on any convenient scale. At b erect a perpendicular, ba. By means of a protractor cut off on ba a number of angles within the probable range of variation of dip, so that a line connecting a and c, for instance, forms an angle of 60° with be, etc. With b as a center and be as a radius, draw a circle through c. This completes the tool for solving the problem. Fig. 2 represents the line of strike of the vein and db the trace of the vertical plane on which the vein is to be plotted with the apparent angle of dip. A° is the angle which this plane makes with the strike. Fig. 3 shows the application of the method: Place line cb of tracing over line db of Fig. 2 and move fore and back until line of strike becomes tangent to the circle. Connect d with the point (a) that marks the true angle of dip as found by measurement in the mine (60° in the case illustrated). The angle adb is the apparent angle of dip (C°) to be used in the vertical section. Proof.-As stated in Mr. Bancroft's paper, the apparent angle of dip is: tan C° = sin A° tan B° (1)

Jan 12, 1914

By D. Moskowitz

IN the course of a general investigation of boride systems, sponsored by the Office of Naval Research, various vanadium boride powders of relatively good purity were prepared which could be used for a determination of the phases present. The X-ray pattern of one of these lots showed, in addition to the known VB1 and VB22 phases, an additional phase, almost certainly of composition V3B4, isomorphous with Cr3B4, Cb3B4, Ta3B4, and Mn3B,. Its pattern fitted in well with the indices worked out by Kiessling for Mr3B4.3 The unit cell for this new compound is orthorhombic, with the dimensions a = 3.030A, b = 13.18A, c = 2.986A7 V=119.2A.' Table I lists the X-ray diffraction data for V.3,.

Jan 1, 1957

By Atmesh K. Sinha

In spite of the artificial supports which are provided to reinforce the mine roof and prevent failures, roof falls continue to occur very frequently in the mines due to the very unpredictable geological conditions and the dynamic nature of the mining operations. In fact, roof fall is still one of the largest contributor to coal mine fatalities. The design of a roof support plan is often based on arbitrary criterions due to the unpredictable behaviour of the rocks under the mining conditions. The failure of a mine roof which ultimately results in a roof fall and contribute to mine hazards, is caused following a gradual degradation in its physical conditions. A mine roof monitoring system capable of monitoring the rate of deterioration of a mine roof on a continuous basis has been developed and tested in an operating coal mine. The monitor can help to improve and supplement the roof support plans and

Jan 1, 1983