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About 1300 members and guests attended the Seventh Annual Mid-winter Convention of the American Institute of Electrical Engineers, which was held in the Engineering Societies' Building, New York, on Feb. 19 to 21. The opening session was a joint session with the American Institute of Mining Engineers, when welding was discussed. The various phases of standardization in engineering work were discussed by President Comfort A. Adams at the Thursday morning session. Thursday afternoon was spent in visiting. Some of the guests visited the Brooklyn Navy Yards, where they inspected the power plant, shops, dry, docks, etc. ; others visited the Bell System Laboratories of the Western Electric Co. The papers at the various technical sessions provoked considerable

Jan 4, 1919

Discussion of the paper of M. E. Lormbardi,. presented at the New York meeting, February, 1915, and printed in Bulletin No. 9S, February, 1915, pp. 209 to 215. I. N. KNAPP, Ardmore, Pa.-Some years ago I made a swinging spider to carry a string of casing in a way somewhat similar to that described in this paper. The ground I tried it in was too soft for its successful operation. The spider had a central one-flange bushing to carry the slips. Under this flange and on top of the spider was a properly protected ball runway, or ball bearing, which permitted rotating the casing when it was in place and supported by the slips.

Jan 5, 1915

W. H. BASSETT, * Waterbury, Conn.-Manganese should not be expected to remedy all the defects that are due to poor melting practice. It is undoubtedly valuable in helping to eliminate porosity in many of the alloys. In the copper-nickel alloys, its use is becoming almost universal, for, beside helping to make sound castings, it tends to hold the carbon in solution in the solidified alloy. GWILLIAM H. CLAMER,? Philadelphia, Pa.-I have found that manganese copper is satisfactory for eliminating sulfur and that it works very well in the crucible and when you have reducing conditions; but in a large reverberatory charge, where the conditions are oxidizing, we were not able to eliminate the sulfur.

Jan 1, 1919

By David A. Rice

This note describes a simple, rapid technique for measuring the apparent volume and density of individual bits of porous materials such as iron ore pellets or pieces of coke. The method consists of determining the weight recorded on a balance when a particle is depressed below the surface of mercury, and calculating the apparent volume from the known density of mercury. The apparent density is calculated after weighing the particle in air. The method is particularly well suited for applications where a great number of determinations are to be made. An additional benefit is the minimal handling of the mercury. In any event, the usual recommended safety precautions should be adhered to.

Jan 1, 1982

C. W. WASHBURNE, New York, N. Y. (communication to the Secretary *).-We are indebted to Mr. Pack for his detailed description of a rapid method of estimating the oil reserves in large fields. Although his method will give only a rough approximation of the reserves, nevertheless it is much more reliable than the saturation method. The saturation method should not be used when any other method is available. The paper describes a generalized method, which is especially useful in estimating the total resources of a Nation or State. Properly it is a method of estimating the oil that can be extracted by common methods within a given period of time. It does not account for

Jan 10, 1917

By C. Ernest Birchenall

TWO recent papers1,2 cite measurements of surface contour changes on copper which, when attributed to surface self-diffusion, can be interpreted to yield activation energies for surface self-diffusion that approach1 or exceed2 those reported for volume self-diffusion in the same metal.3 It is acknowledged2 that AS must be assigned much too large a value to be physically reasonable in order to make the theoretical Do's agree with the experimental values, if the jump distance is of the order of the interatomic distance. However, long jumps would probably lead to marked anisotropy on planes that consist of ridges and valleys (like (110) in fcc) whereas only mild

Jan 1, 1963

By Roswell Johnson

THE prevailing system of wells on a rectangular basis, as shown in Fig. 1-A, has developed because of the exigencies of offsetting at boundary lines. When, however, a very large tract is, being drilled, it is often possible to abandon this inferior method for the superior arrangement C- PROPER STAGGERING FIG. 1.-THREE SYSTEMS OF SPACING WELLS. known as "staggering," which is illustrated in Fig. 1, B and C. The advantages of the triangular over the rectangular method are evident from Fig. 2, computed on the basis of one well to 10 acres (4 ha.). With the triangular system, no land is more than 409.4 ft. (124.8 m.) from a

Jan 8, 1918

By J. H. Wernick

IN a study of the rate of decomposition of ½ -in. cubes of limestone, dolomitic limestone, and dolomite in a sweeping nitrogen atmosphere, Joseph, Beatty, and Bitsianesl found that the zone of calcination advanced at substantially a constant rate at a given temperature. The purpose of this paper is to show that their data indicate at least two processes occurring when the above carbonates decompose. It is suggested that there are two processes occurring temperature range and the other the limiting process over another temperature range. The data of Joseph and co-workers have been extended by use of the Arrhenius equation, Eq. 1, a relation beween the velocity constant k of a reaction and the absolute temperature T.

Jan 7, 1954

By K. D. Weverstad, J. E. Cleveland, J. C. Franklin, J. W. Black

A mined-out stope being backfilled with classified mill tailings was continuously monitored, both upstream and downstream, to determine the radon concentration associated with the mill tailings. The radon monitoring was done before, during, and after the backfill operation. Data taken during weekends when no mining activities were influencing the radon concentration showed a 90 percent reduction in radon discharge from the stope after being backfilled. Water used to mix with the classified sands showed an increase in the heavy metals concentration immediately after seeping from the inplace sand. However, the water used in backfilling is less than ½ of 1 percent of total mine water discharged. The change in contamination is not measurable at the pumping station.

Jan 1, 1982

By U. Max, P. R. Geoffroy, J. A. Lawrence

When shaft sinking was begun on the Vendome Mines property in the Barraute area of north-western Quebec, there was no indication of the flat mud seam that was later encountered, and no special precautions were taken in applying conventional methods of grouting. Failure of the first cementing attempt emphasized the important fact that mud is an adverse condition in grouting. A method was then devised that would remove the clay from those portions of the seam adjacent to the shaft, replacing it by a bulky mixture of cement and sawdust. Tests were carried out to insure that the seam had been properly sealed and that excavation could be resumed without endangering the shaft.

Nov 1, 1955

By R. Maddi, I. R. Kramer

C. S. Roberts (Dow Chemical Co., Midland, Mich.)— In this study we have seen another example of how modern electronic instrumentation can be of great value to metallurgical research. The authors have shown much ingenuity in their experimental work. However, I wish to point out that anelasticity theory tells us that we must be cautious when we use pulse methods for measurements which are to be correlated with knowledge of static stress-strain behavior. The basic stress calibrations used by the authors depend on the use of static moduli combined with the pulsed strains. No recognition of a possible modulus defect has been indicated. The general agreement of critical resolved shear stresses may indicate that a

Jan 1, 1953

Denver, the Mile High, Queen City of the Plains, your host for AIME's 99th Annual Meeting has many exciting and picturesque places for you to visit during your stay. A host of restaurants cater to every taste; supper clubs and theaters provide nighttime entertainment; there are sports facilities and a plethora of shops for the ladies. When it comes to dining out, there are many excellent restaurants within walking distance of the Denver Hilton --among them, three in Brooks Towers: the Gitana, the Boston Half Shell serving the finest seafood, and Marvelous Mary's. In the Larimer Square area there in the Bratskellar with a true Germanic atmosphere and Sperte's Laffite offering a typical New Orleans setting.

Jan 1, 1970

By M. R. Moharam

The well-known formulae of screening efficiency and circulating load calculations in closed crushing circuits were exploited to achieve graphical estimation of these parameters. Three basic charts were proposed and constructed. The first one is for the regular closed circuits where the new feed goes to the crusher. The second is for the reverse closed circuits in which the new feed reported to the screen is free of screen undersize particles. The third chart controls the reverse circuits when they are receiving new incoming feeds containing undersize material. Compound circuits were also reanalyzed and a concept of equivalent simple circuit was introduced to enable graphical manipulation of these complex circuits with the help of the aforementioned charts

Jan 1, 1982

By R. W. Raymond

Some months ago I heard from a party of returned tourists an amusing story of a Chinese laundryman in the National Park who had included in his cabin a hot spring, of which he was accustomed to avail himself in his business, and who, on one occasion, having thrown a lot of linen into this spring to soak overnight, had added a piece of soap to facilitate the process, and had been considerably surprised when, stimulated by this soap, the spring had suddenly become a geyser and wrecked his establishment. The story went on to say that the practice of "soaping" geysers to make them, active had become general, but had been forbidden by the authorities.

Jan 1, 1889

By Mark T. Atwood, Franklin B. Carlson, Louis H. Yardumian

The Oil Shale Corp. (TOSCO) is investigating the application of its oil shale retorting technology to coal processing in its 25-tpd retorting pilot plant. Low temperature char, with a high heating value, plus tar and gas have been produced from high moisture content, low heating value, subbituminous coal. The process, which has been named the TOSCOAL process, uses heated ceramic balls to provide the heat for retorting the coal. One ton of as-mined, subbituminous coal produces approximately 1/2 ton of char, 1/2 barrel of tar, and 1600 standard cubic feet (scf) of gas when the retorting is conducted at 970°F. Properties and yields of the products are presented and compared with Fischer assay yields.

Jan 1, 1975

By Douglas A. Anderson

We have instrumented well-controlled free-face blasts with six- component borehole strain gages, in order to determine the complete strain tensor as a function of time due to explosive loading. The strain tensors have been diagonalized to determine the principal strain time-histories, and further processed to determine the octahedral shear strains as a function of time. Principal strain time-histories, when compared with a computer model, indicate the arrival of various direct and reflected phases. Strong shear strains coincide with the expected arrival time of shear waves. These shear waves are probably instrumental in the fragmentation of confined rock due to explosive loading, and should be incorporated in models of the fragmentation process.

Jan 1, 1984

By P. K. Koh, L. S. Birks, J. M. Siomkajlo

Direct identification in situ of x and a phase precipitates in stainless steel is possible with the electron probe microanalyzer. Although particles in the 1 p size range are too small to yield absolute percent composition, the relative % Crfi Mo ratio can be used to distinguish the two phases with better than 95 pct confidence. Wet chemical analysis of extracted residues gives Cr/Mo ratios in good agreement with electron probe results extrapolated to the 4 to 5 p size range. WHEN stainless steels are subjected to extended heating in the temperature region around 1600°F, precipitation of the brittle 0 or x phases may occur and impair the properties of the material. Identi-

Jan 1, 1961

By Byron W. Cheever

Of the elements found in iron and steel, none has attracted more attention than phosphorus. It is considered the great enemy of the steel manufacturer-, and the chief aim has been and is to keep it out by using pure crude material, or when once in, to eliminate it or counteract its effect. Its presence is manifested in various ways, but most of all by producing a condition called cold-shortness. The first question, then, which presents itself is, What per cent. of phosphorus produces this condition ? I have searched very carefully for an answer to this question, but have failed to find one. Authors generally agree that wrought-iron may have a larger per

Jan 1, 1887

By Michael Chender

The current outlook for financing new copper production is not very encouraging. At a time when companies are slogging through a protracted period of low prices as well as having to accept lower profits due to more stringent tax and royalty schedules, banks are beginning to require companies to take a greater equity interest in new projects. Mineral resource financing, including copper, seems to have lost much of its appeal to the lending institutions, and loans of any kind to many of the developing countries -from which over half of new copper capacity could be expected to come-are being examined much more critically than they were in the late 1960's and early 1970's.

Jan 12, 1976

By E. K. Olson

Eagle Mountain mine of Kaiser Steel Corp. began production in 1947 when the direct shipping ore contained 51-56% Fe. The high grade, wide ore face and low stripping ratio ores were rapidly depleted and Eagle Mountain required processing plants for upgrading and more efficient mining equipment. During 1970-71 total annual pit tonnage averaged 56 million tons of material ranking the Eagle Mountain Mine as the fourth largest in the country. Ore production averaged 12.5 million tons requiring a stripping ratio of 3.5: 1. During this period mining activities were scheduled for a three-shift, seven-day operation. The present mining rate is about 30 million tpy on a two-shift, five-day schedule.

Jan 12, 1972