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By Rossiter W. Raymond

(Read at the Amenia Meeting, October, 1877.) IN the case of The Eureka Consolidated Mining Company v. The Richmond Mining Company of Nevada, recently tried at San Francisco, California, the real defendant was the Richmond Consolidated Mining Company, of London; but this being a foreign corporation, holds its mining property in Nevada through the Nevada corporation of similar name, in which the London Company owns all the stock, except the few shares necessary to "qualify" the American directors. The trial would naturally have taken place in the Circuit Court at Carson City, Nevada, and before a jury. But by stipulation of the parties, the case was tried in San Francisco, before Hon. Stephen J. Field, Justice of the Supreme Court of the United States, Hon. Lorenzo Sawyer, United States Circuit Judge of the Ninth Circuit, and Hon. E. W. Hillyer, United States District Judge, for the District of Nevada. The hearing began July 23d, 1877. The witnesses occupied two weeks, and the argument of. counsel three days. Very eminent lawyers were. engaged on both sides ; for the plaintiff, Messrs. Solomon Heydenfeldt, R. S. Mesick, John Garber, and H. J. Thornton ; for the defendant, Messrs. S. M. Wilson, Thomas Wren, and J. J. Williams. The court held the case under advisement until August 22d, when Mr. Justice Field delivered its unanimous opinion in favor of the plaintiff. The action was a complaint in ejectment, and an appeal was taken to the United States Supreme Court. The questions at issue between the Eureka and the Richmond Company in this suit, comprised several points in the construction of the mining law of the United States, and its relation to the customs and regulations of the mining districts, which possess an importance and an applicability far beyond the limits of the case in which they arose. It is my purpose to state these points, the arguments

Jan 1, 1878

By Milton E. Wadsworth, T. D. Chatwin

Bulk density variations can usually be minimized by properly mixing the material before moisture measurement. The measuring of moisture on material being with- drawn directly from storage bins requires some form of bulk density correction. In Bethlehem's pellet plants continuous automatic bulk density correction and uniform feed-rate control are obtained with Bethlehem's patented Bin Level Control System. With this sys- tem a single probe, suspended or inserted in the bin, senses whether material is at the proper level in the bin and automatically regulates filter speed to control the filter-cake discharge rate to maintain this level. The level of concentrate in the filter-cake bin can thereby be controlled to within ± 1/2 in. of the point of contact between the concentrate and the probe. Material thickness on the conveyor does not have to be controlled accurately and mix compositions can vary widely as long as they do not contain variable amounts of water-soluble electrolytes. In sinter plants, errors caused by changes in normal feed rate and bed height are minimized by counter-weights that permit the free-floating to maintain a uniform contact pressure on the mix. Large changes in mix resistance can be taken care of either by resetting the control point or by adjusting the calibration control.

Jan 9, 1968

By V. Leroy, A. G. Guy

Serious disagreements are often found between experimentally determined intrinsic diffusion coefficients and those calculated employing the usual form of the vacancy theory. In the new theory it is proposed that the total intrinsic flux, Ji, of component i, is the sum of a part, f, due to the usual random exclzanges of component i with the vacancies, and a second part, Ji, due to exchanges with the uacancies composing the net vacancy flux. The present treatment, while less powerful than that of Manning, has the advantage of easy uisualization and of facilitating the application of the vacancy-flux effect to complex systems. IT is becoming increasingly evident that there are serious deficiencies in the version of the vacancy theory of diffusion that has been widely used for the past 20 years. One type of evidence is the frequent lack of agreement between intrinsic diffusion coefficients and tracer diffusion coefficients, even taking account of the thermodynamic factor. A second kind of evidence is the observation of a Kirkendall shift larger than theoretically possible, that is, larger than can be accounted for without assigning a negative value to one of the two intrinsic diffusion coefficient.'- The thermodynamic factor could conceivably make both coefficients negative, but not just one. It is clear that a cause of these anomalies, apart from any inadequacy of the usual vacancy theory, might lie in an oversimplified treatment of the data. Adequate experimental techniques, including the use of moderate pressure during the diffusion anneal, are now available to insure that porosity, lateral expansion, and so forth, can be kept negligibly small in most cases. The effect of differences in atomic volume can be of major importance, and it is essential that one of the available methods4 be used to account for this factor. In the present treatment this is accomplished by the consistent use of moles per cubic centimeter as the unit of concentration. Of the various possible inadequacies of the vacancy theory, attention will be given here only to effects of the net vacancy flux. annin' has previously considered this question, beginning with an analysis of atomic jumping of tracer atoms. When he added the effect of a concentration gradient, new terms arose that could be associated with the flow of vacancies. The present treatment uses quite a different approach. The usual vacancy flux, J,, is introduced explicitly, and a simple analysis predicts major changes in the intrinsic diffusion coefficients from this cause. The usual assumptions are made that only a vacancy mechanism is operative, that the formation of voids can be neglected, and that changes in the partial molal volumes, vl and v2, are negligible. The significant diffusion coefficients for the present topic are Dl and D,, the intrinsic coefficients, which enter in the equations, where the flux Ji, moles per sq cm per sec, is that crossing the Kirkendall interface. The concentration, ci, is in units of moles per cu cm, and the concentration gradient, aci/ax, is evaluated at the Kirkendall interface. It will be recalled' that the calculation of Dl and D2 involves the measurement of areas on the diffusion curve with respect to the positions of the Kirkendall and Matano interfaces. In the case of the anomalies mentioned earlier, the Kirkendall shift is too large to be accounted for by the diiferetzce in fluxes (J2 -J1), given by Eqs. [I] and [2]. The logical inference is that the flux of the solvent atoms, J1, is actually in the same direction as the flux of the solute atoms, Jz. In terms of Eq. [I] this requires that Dl have a negative value. However, it would be somewhat misleading to state that the solvent atoms are diffusing up their own concentration gradient. The explanation that will be advanced here pictures competing processes producing the net flux of solvent atoms: 1) diffusion of the solvent atoms down their own gradient by random exchanges with vacancies; and 2) diffusion of solvent atoms in the opposite direction by exchanges with the net vacancy flux. ACTION OF THE NET VACANCY FLUX Theories of vacancy diffusion can be formulated with varying degrees of refinement, and the present theory has purposely been kept as simple as appeared adequate to explain the phenomenon in question. In particular the following aspects have been neglected: 1) the gradient of vacancy concentration in comparison to the gradient of the atomic species; 2) departure of vacancy concentration from the local equilibrium value; 3) variation of the jump frequency, LO, with the specific surroundings of the atom-vacancy pair being considered; 4) correlation effects. These and other refinements can be considered once the essential mechanism has been established. The essential idea of the present analysis is to calculate the total intrinsic flux, Ji, of component i as the sum, JlJ?±j{ [3] where J; is attributable to the usual random atomic jumping, and J{ is a contribution arising from the net vacancy flux, J,. The latter quantity, of course,

Jan 1, 1967

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 T. B. Massalski, Horace Pops

Martensitic transformations were observed by optical metallography and electrical-resistivity measurements during cooling at cryogenic temperatures of the bcc pr-phase Au-Zn alloys. The com-position dependence of the MS, MF, AS , and AF temperatures have been determined. It is concluded that the martensitic platelets which grow mainly in the lengthwise direction and which are associated with a very small temperature hysteresis are "thermoelastic" martensite. In some cases the observed structure seems to have no definite crys-tallographic habit or consists of a mixture of- plates and broad transformed areas. THE majority of the bcc /3-phase alloys in systems of copper, silver, and gold with zinc and cadmium are unstable at low temperatures and undergo a transformation upon further cooling into another structure. A large number of such transformations are martensitic. The composition dependence of the Ms temperatures has been determined and reported for CU-~n,' Ag-Cd,' and AU-C~~ alloys. The 50 at. pct ordered Au-Zn p' alloy has been reported by Jan and pearson4 to transform martensitically at 58°K in connection with their study of the de Haas-van Alphen effect The p' phase in the Au-Zn system has the ordered CsC1-type structure. The phase field is shown in Fig. 1: it has the typical V shape which is characteristic of all copper-, silver-, and gold-based binary /3-phase alloys. There appears to be no a priori reason why the transformation should be limited to the equiatomic composition and the availability of a cryogenic stage for optical metallography5 has permitted studies down to the liquid-helium temperature of a series of alloys in this system. EXPERIMENTAL PROCEDURE Predetermined weights of 99.999 pct pure gold and zinc were melted and cast under a partial atmosphere of helium in sealed quartz capsules. Thorough mixing of the molten metals was achieved by vigorous shaking, followed by a rapid quench into a brine solution. All ingots were homogenized at 640°C for 4 days. The loss in weight was usually less than 0.04 wt pct and was assumed to be due to

Jan 1, 1965

Some Things We Don't Know about the Creep of Metals. By H. W. Gillett (T.P. 1087) Reduction of Iron Ores under Pressure by Hydrogen. By Michael Tenenbaum and T. L. Joseph (T.P. loll, with discussion) Induction Furnaces for Rotating Liquid Crucibles. By E. P. Barrett, W. F. Hol- bRook and C. E. Wood (T.P. 986, with discussion) Mechanism of Solidification and Segregation in a Low-carbon Rimming-steel Ingot,. By Anson Hayes and John Chipman (T.P. 988, with discussion) Solidification of Rimming-steel Ingots. By A. HultGRen and G. PhRagmen. (Contribution 112) Dendritic Structure of Some Alloy Steels. By Daniel .I. Martin and James L. Martin (T.P. 1066, with discussion) Occlusion and Evolution of Hydrogen by Pure Iron. By George A. Moore and Donald P. Smith (T.P. 1065, with discussion) Structure of Iron after Con~pression. Hy Charles S. Barrett (T.P. 977, with discussion) Structure of Iron after Drawing, Swaging, and Elongating in Tension. Ry Charles S. Barrett and L. H. LevensoN (T.P. 1038, with discussion) Magnetic Torque Studies of the Texture of Cold-rolled and of Recrystallized Iron-silicon Alloys. By Leo P. TaraSovJ(T.P. 1012, with discussion) Influence of Atmosphere and Pressure on Structure of Iron-carbon-silicon Alloys. By Alfred Boyles (T.P. 1046) Kinetics of the Decomposition of Austenite at Constant Temperature. By J. H. Austin and R. L. Rickett (T.P. 964, with discussion) Reaction Kinctics in Processes of Nucleation and Growth. By William A. Johnson and Robert F. Mehl (T.P. 1089, with discussion) Phase Changes in 3.5 Per Cent Nickel Steel in the Acl Region. By I. N. Bavarine (T.P. 1031, with discussion) Chromium in Structural Steel. By Walter Crafts (T.P. 1055) Surface Allotropic Transformation in Stainless Steel Induced by Polishing. By J. T. BuHwell and J. WUlff (T.P. 1032, with discussion) Nature of :Passivity in Stainless Steels and Other Alloys, I and 11. Ry H. H. Uhlig and John WUlff (T.P. 1050, with discussion) Thermal Expansion of Nickel-iron Alloys (Nickel from 30 to 70 Per Cent). Ry J. M. Lohr and Charles H. Hopkins (T.P. 987, with discussion) Low-temperature Transformation in Iron-nickel-cobalt Alloys. By L. L. Wy~Ian (T.P. 1013, with discussion) Fracture of Steels at Elevated Temperatures after Prolonged Loading. By R. H. Thielemann and E. R. Parker (T.P. 1034, with discussion)

Jan 1, 1939

Some Things We Don't Know about the Creep of Metals. By H. W. Gillett (T.P. 1087) Reduction of Iron Ores under Pressure by Hydrogen. By Michael Tenenbaum and T. L. Joseph (T.P. loll, with discussion) Induction Furnaces for Rotating Liquid Crucibles. By E. P. Barrett, W. F. Hol- bRook and C. E. Wood (T.P. 986, with discussion) Mechanism of Solidification and Segregation in a Low-carbon Rimming-steel Ingot,. By Anson Hayes and John Chipman (T.P. 988, with discussion) Solidification of Rimming-steel Ingots. By A. HultGRen and G. PhRagmen. (Contribution 112) Dendritic Structure of Some Alloy Steels. By Daniel .I. Martin and James L. Martin (T.P. 1066, with discussion) Occlusion and Evolution of Hydrogen by Pure Iron. By George A. Moore and Donald P. Smith (T.P. 1065, with discussion) Structure of Iron after Con~pression. Hy Charles S. Barrett (T.P. 977, with discussion) Structure of Iron after Drawing, Swaging, and Elongating in Tension. Ry Charles S. Barrett and L. H. LevensoN (T.P. 1038, with discussion) Magnetic Torque Studies of the Texture of Cold-rolled and of Recrystallized Iron-silicon Alloys. By Leo P. TaraSovJ(T.P. 1012, with discussion) Influence of Atmosphere and Pressure on Structure of Iron-carbon-silicon Alloys. By Alfred Boyles (T.P. 1046) Kinetics of the Decomposition of Austenite at Constant Temperature. By J. H. Austin and R. L. Rickett (T.P. 964, with discussion) Reaction Kinctics in Processes of Nucleation and Growth. By William A. Johnson and Robert F. Mehl (T.P. 1089, with discussion) Phase Changes in 3.5 Per Cent Nickel Steel in the Acl Region. By I. N. Bavarine (T.P. 1031, with discussion) Chromium in Structural Steel. By Walter Crafts (T.P. 1055) Surface Allotropic Transformation in Stainless Steel Induced by Polishing. By J. T. BuHwell and J. WUlff (T.P. 1032, with discussion) Nature of :Passivity in Stainless Steels and Other Alloys, I and 11. Ry H. H. Uhlig and John WUlff (T.P. 1050, with discussion) Thermal Expansion of Nickel-iron Alloys (Nickel from 30 to 70 Per Cent). Ry J. M. Lohr and Charles H. Hopkins (T.P. 987, with discussion) Low-temperature Transformation in Iron-nickel-cobalt Alloys. By L. L. Wy~Ian (T.P. 1013, with discussion) Fracture of Steels at Elevated Temperatures after Prolonged Loading. By R. H. Thielemann and E. R. Parker (T.P. 1034, with discussion)

Jan 1, 1939

Discussion of the paper of Frank H. Kneeland, Safeguarding the Use of Mining Machinery. By B. F. Tillson and Arthur Williams. 1073 Discussion of the paper of Howard N. Eavenson, Safety Methods and Organization of United States Coal & Coke Co. By William H. Grady, Thomas W. Dawson, C. W. Goodale, J. Parke Charming, B. F. Tillson, George S. Rice, Arthur Hovey Storrs, Harry H. Stoek, Lawson Blenkinsopp, Arthur Williams, and Howard N. Eavenson. 1075 Discussion of the paper of J. Parke Channing, Enlarging the Worth of the Worker and the Perspective of the Employer. By Fred H. Rindge, Jr., S. A. Taylor, Elmer L. Corthell, and Philip W. Henry. . 1095 Discussion of the paper of Walther Mathesius, High Blast Heats in Mesaba Practice. By Joseph W. Richards, W. A. Forbes, J. E. Johnson, Jr., H. P. Howland, and Walther Mathesius. . 1100 Discussion of the paper of W. R. Shinier, Effect of Finishing Temperatures of Rails on Their Physical Properties and Microstructure. By William R. Webster, Henry M. Howe, A. A. Stevenson, G. K. Burgess, and Samuel L. Hoyt . 1107 Discussion of the paper of George K. Burgess and Sir Robert A. Hadfield, Sound Steel Ingots and Rails. By Albert Sauveur, Henry M. Howe, Henry D. Hibbard, Joseph W. Richards, F. W. Wood, and George K. Burgess. . 1112 Discussion of the paper of Henry M. Howe and Arthur G. Levy, Are the Deformation Lines in Manganese Steel Twins or Slip Bands? By J. E. Stead 1116 Discussion of the paper of F. C. Langenberg and R. G. Webber, Structures and Hysteresis Loss in Medium-Carbon Steel. By Henry M. Howe. . . 1117 Discussion of the paper of Charles H. MacDowell, German and Other Sources of Potash Supply. By George S. Rice, Charles H. MacDowell, and V.C. Grubnau . . 1118 Discussion of the paper of Joel H. Watkins, White-Burning Clays of the Southern Appalachian States. By H. Ries 1120

Jan 5, 1915

By G. Y. Chin, W. L. Mammel

The problem of selection of the active slip systems for a crystal undergoing an arbitrary strain has been analyzed by Taylor and by Bishop and Hill. The Taylor analysis is based on a principle of' virtual work, and involves finding, among numerous cotnbinalions of slip systems that satisfy the imposed strain, the combination in which the sum of the glide shears is a minimum. Previously, Taylor has treated the case of axisymmetric flow when slip occurs on (111)(110) (or {110)(111)) systems only. His analysis has now been extended by computer methods to the cases of slip on {112}(111) and {123)(111) systerns and of mixed slip on {110), {1 12), and (123) planes with a common (111) slip direction, all of which are important in the deformation of bcc crystals. The results are computer-plotted as contours of the ratio of the floe strength to the critical resolved slzea-r stress for slip, for axial orientations distributed throughout the standard stereographic triangle. Implications of the computer results to texture develop,merit, texture hardening, and dislocation theories oj work hardening are discussed. WhEN a single crystal is extended in the usual tension test, the lateral dimensions can change relatively freely. In this case, the glide shear produced by slip on a single slip system is sufficient to accommodate the (tensile) deformation. Since slip is governed by a critical resolved shear stress law (the Schmid law'), the single active slip system is one for which the stress, resolved on the slip plane and in the slip direction, is the highest among the several equivalent slip systems. This amounts to saying that a value M = U/t = y/~ is a minimum among the equivalent systems, where M is the inverse of the familiar Schmid factor (a and E refer to tensile stress and strain, and T and y refer to resolved shear stress and shear strain). A grain embedded in a polycrystalline aggregate, on the other hand, cannot freely change its shape due to constraint from its neighbors. In this case, slip from five independent slip systems (to accommodate five independent strains) is generally required.' Based on the principle of virtual work and assuming that the critical resolved shear stress for slip is the same for all systems, Taylor hypothesized that, among all combinations of (five) slip systems which are capable of accommodating the imposed strain, the active combination is that one for which the sum of the absolute values of the glide shears is a minimum. Again, this is equivalent to saying that the value of M = CjlyjI/ is a minimum, in analogy to the single slip case. Taylor aminimum,analyzed the case of {111)(110) slip for fcc metals, and applied the analysis to crystals undergoing axisymmetric flow, that is, the same macroscopic shape change as the poly crystalline aggregate under uniaxial tension (or compression). For the twelve equivalent {111}( 110) slip systems, there are 384 independent combinations of selecting five systems to satisfy the five independent linear equations of imposed strain.4 Taylor calculated the value of M for each combination* and obtained the active com- *A number of the independent combinations were omitted from consideration in Taylor's original work (see Ref. 5). bination (minimum M) for a number of axial orientations distributed throughout the standard stereographic triangle. Later work by Bishop and Hill*'8 showed that Taylor's least-shear hypothesis was equivalent to a maximum work principle which they advanced. Using the simplified Bishop and Hill method for {111)(110) slip, Hosford and Backofen' obtained detailed contours of constant minimum M for the same axisymmetric flow case. In contrast to {111}(110) slip in fcc metals, slip in bcc metals is generally described as occurring on {ll~)(lll), {112)(111), {123) (111) systems as well as mixed slip composed of all three. Since the direction cosines of the slip plane normal and the slip direction enter as a product in the Taylor analysis, the Taylor solutions of ,M for {110)(111) slip are identical to those for { 111} 110) slip. The other three cases of slip, however, have not been solved. In view of the numerous combinations of slip systems involved in the calculations, the Taylor analysis is clearly oriented toward computerized solutions. THE TAYLOR ANALYSIS In order to obtain the active combination of (five) slip systems by solving for the minimum value of M = we first express the (small) strain components E,, with respect to the cubic axes 1, 2, 3 ([loo], [010], [001], respectively) of the crystal, in terms of the sum of the glide shears yj from slip systems j: where n, and n,j refer to direction cosines of the slip plane normal, and dri and dsi to direction cosines of the slip direction, of slip system j, all referred to the cubic axes. In practice, the strain components are given with respect to the specimen axes X, y, 2. These components are readily converted to ers through the tensor transformation where irk and 1,~ are the direction cosines between the two sets of coordinate axes.

Jan 1, 1968

By H. L. TERWILLIGER

THOSE of us who have been following rock drilling work for the last 15 or 20 years can recall some of the problems that were encountered with the old piston type of rock drill and the solid steel which it used. There was frequent trouble in keeping a straight hole in badly broken ground when using the ordinary four- point bit that had a flare on the wings of about 14". The drill steel, when pounding down its hole, would follow the line of least resistance and draw away from the desired line when it encountered a weak side in the ground through which it was drilling. Some would overcome the difficulty by making long winged bits to prevent the steel crowding over; this would relieve the troubles to a great extent. There was trouble with the rifling of drill holes and inability to drill round holes in some ground. The cure for these ills was to use the "X" bit, rather than the crossbit. The "2" bits were brought out in an effort to make it easier to drill a round hole in bad ground. Most of these troubles were before the days when the mechanical drill sharpener was in as common use as it is today. It was not until the introduction of the Leyner type of rock drill, requiring hollow steel that the users of rock drills found themselves confronted with more difficult prob- lems than they had ever encountered before with drill steel because the steel had to stand more severe service.

Jan 1, 1924

By A. T. Yu

As the first loads of Noamundi iron ore rumbled into the new 54-in. Gyratory Crusher on March 30, 1968, one of India's largest and most modern iron ore processing complexes began operations. The completion of the $13 million mining and processing complex brought to a successful conclusion the second chapter of a phased expansion program initiated in 1958 by India's gigantic Tata Iron and Steel Co. The completed complex will yield annually 2.5 million tons of washed, sized ore and sinter fines destined for Tata's furnaces at Jamshedpur. Hewitt-Robins Div. of Litton Industries was awarded the turnkey project on the basis of world- wide competitive bids. Eighty miles southwest of the city of Jamshedpur, Noamundi lies on an approximate geographic grid of 22º-5' latitude north and 85º-30' longitude east. The mine is approximately 600 ft above sea level.

Jan 11, 1968

[59H1-Water Law and Its Significance to the Mining Industry by Wells A Hutchins 59H2-Relation of Land Subsidence to Groundwater Withdrawals in the Upper Gulf Coast Region, Texas by Leonard A Wood and A G Winslow 59F3-Hydraulic Mining of Gilsonite and Its Application to Coal Mining by J H Baker 59H4-Recovery of Phosphates by In Situ Fluid Mining by Sylvain J Pirson 59F5-Coal Cleaning Plant Design for Minimum Operating Labor by Wm M Bertholf and John D Price 59F6-Coke Combustibility A Neglected Characteristic by J D Price 59B7-Union Carbide's Uranium Operation at Maybell, Colorado by K W Lentz and F T Temple 59H8-A Rapid Method for Estimating Alumina in Feldspathic Sands by Hugh H Bein 59H9-Water Laws as Related to Dredging in Idaho by Robert A Lothrop, Richard B Porter, and Robert P Porter 58B19-Separation and Washing of Alumina Process Residue by Morton Handelman 59B11-Feed Preparation and Froth Modification for Fatty Acid Flotation by Carl C Martin and Burt C Mariacher 59B12-Design Requirements for Tailing Disposal in the Southwest by E Vern Given 59B13-Semi-Dome Shaped Buildings for Bulk Storage by Edward E Ives and William L Payne]

Jan 1, 1961

(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.) ANDERSON, AMIL A., Co. A, 309th Regiment Engineers, 84th Div., American E. F., Care Postmaster, New York. ARMSTRONG, HAROLD K., Pilot, Naval Aviation, U. S. Naval Air Station, Miami, Fla. BASSETT, ARTHUR F., Co. 6, -E. 0. T. S., Camp Humphreys, Va. BEDDALL, THOMAS H., Adjutant, 1st Battalion, 1st Gas Regiment, American E. F. BERNARD, CLINTON P., Candidate, 12th Observation Battery, F. A. C. 0. T. S., Camp Taylor, Ky. BROOKE, LIONEL, 50th Co., 13th Battalion, 5th Replacement Engineers, Camp Gordon, Ga. BROWNING, EDWARD, Corp., 1st Regiment Engineers, Co. D, American E. F. BUGBEE, EDWARD E., S. A. T. C. Headquarters, Raleigh N. C. BUTTERFIELD, G. BRUCE, CO. C, 605th Engineers, American E. F. CADOT, J. J., 1st Lieut., U. S. Air Service, American E. F., Care Post- master, New York. CARLOCK, J. B., Major, 2d Battalion, 1st Gas Regiment, American E. F., France.

Jan 12, 1918

The first session of the Institute was held at the Smithsonian Institution, on Tuesday evening, February 22d. The members were welcomed to Washington and to the Smithsonian by Prof. Joseph Henry. President Holley responded to the cordial welcome of Professor Henry, and then read an introductory address on the subject of Technical Education. Following the discussion on President Holley's address the following persons, duly proposed and indorsed by the Council, were elected members and associates of the Institute : MEMBERS. Emile R. Abadie,. .. .. St. Louis, Mo. R. J. Anderson,.....Pittsburgh, Pa. Commander L. A. Beardslee,. .. Washington, D. O, Charles Bender,. .. .. New York City. Charming M. Bolton,. .. . Richmond, Va. Thomas E. Bowman,. .. . Silverton, Colorado. Calvin E. Brodhead,. .. . Bethlehem, Pa. M. L. Brosius,. .. .. . Lewistown, Pa. Harvey H. Brown,. .. .. Cleveland, Ohio. James A. Burden,.. .. . Troy, N. Y. J. P. Clemes,. .. .. . Sonora, Mexico. N. H. Cone,. .. .. . Nederland, Colorado. W. F. Durfee,.. .. . New York City. Robert Frazer, Jr.,. .. . Ashland, Pa, Joseph E. Galigher,.. .. . Bingham, Utah. William Golding,.. .. . Steel Works P. O, Pa. Samuel E. Griscom,.. .. . Pottsville, Pa. Gen. E. Burd Grubb,.. .. Beverly, N. J, Arthur R. Guerard,. .. .. Charleston, S. C. Edward Hart,.. .. .. Easton, Pa. Prof. Lewis M. Haupt,. .. . Philadelphia. E. S. Hawley,.....Buffalo, N. Y. John W. Hoffman,.. .. .. Philadelphia. Nelson P. Hulst,.. .. . Milwaukee, Wis. H. C. Humphrey,.. .. . Philadelphia. Ed. P. Jennings,.. .. .Ithaca, N. Y. B. F. Jones,......Pittsburgh, Pa.

THE first session of the Institute was held at the Smithsonian Institution, on Tuesday evening, February 22d. The members were welcomed to Washington and to the Smithsonian by Prof. Joseph Henry. President Holley responded to the cordial welcome of Professor Henry, and then read an introductory address on the subject of Technical Education. Following the discussion on President Holley's address the following persons, duly proposed and indorsed by the Council, were elected members and associates of the Institute : MEMBERS. Emile R. Abadie, - St. Louis, Ma. R. J. Anderson, - Pittsburgh, Pa. Commander L. A. Beardslee, - Washington, D. C. Charles Bender, - New York City. Channing M. Bolton, - Richmond, Va. Thomas E. Bowman, - Silverton, Colorado. Calvin E. Brodhead, - Bethlehem, Pa. M. L. Brosius, - Lewistown, Pa. Harvey H. Brown, - Cleveland, Ohio. James A. Burden, - Troy, N. Y. J. P. Clemes, - Sonora, Mexico. N. H. Cone, - Nederland, Colorado. W. F. Durfee, - New York City. Robert Frazer, Jr., - Ashland, Pa. Joseph E. Galigher, - Bingham, Utah. William Golding, - Steel Works P. O., Pa. Samuel E. Griscom, - Pottsville, Pa. Gen. E. Burd Grubb, - Beverly, N. J. Arthur R. Guerard, - Charleston, S. C. Edward Hart, - Easton, Pa. Prof. Lewis M. Haupt, - Philadelphia. . R. S. Hawley, - Buffalo, N.Y. John W. Hoffman, - Philadelphia. Nelson P. Hulst, - Milwaukee, Wis. H. C. Humphrey, - Philadelphia. Ed. P. Jennings, - Ithaca, N. Y. B. F. Jones, - Pittsburgh, Pa.

Jan 1, 1876

By W. H. Blauvelt

THE subject of fuel-briquetting has attracted much attention on the part of engineers and investors for the past 15 or 20 years, and especially in recent years, during which a number of plants have been built, with more or less commercial and technical success. Our technical literature contains numerous descriptions of certain processes, and discussions of the industry in general. For a history of the development of the art in the United States, and for descriptions of many of the processes which have been tried, reference may be made to the files of our Transactions, and, for more recent information, to a paper by C. T. Malcolmson, read before the First Annual Convention of the International Railway Fuel Association in June, 1909. The purpose of the present paper is to describe the briquette-plant of the Solvay Process Co. and the Semet-Solvay Co. at Detroit, Mich., which, after a period of long and costly evolution, is now operating satisfactorily on a commercial basis. I believe that it will be of interest to some of our members to have the details of operation, lower-consumption, labor, etc., as worked out on a practical and commercial scale in a going operation. The briquette industry has had a somewhat checkered career in the United States, and much the larger portion of the failures has been due entirely to commercial causes. It seems axiomatic to say that before undertaking the installation of a plant for manufacturing briquettes it is necessary that the local situation should be carefully examined : First, to determine the kind of briquettes, if any, the local market will consume; that is-to say, whether the available fuel-supply is such that briquettes would be a welcome addition, and whether the most promising field is the industrial or the domestic market. Second, if there is an available supply of raw material, as coal,

Mar 1, 1910

By Charles Will Wright

I. INTRODUCTION. THE application of the camera as an adjunct to topographic mapping began practically with its invention, and it has been employed with varying success since that time. With the exception of the camera to be described, the plate-camera has been universally used in this work, thus giving a projection of the area photographed on a flat surface. From such projections or photographs, by the rules of geometry and of perspective, points defining topographic features and seen from at least two camera-stations may be projected upon a ground-plane-the map.1 In 1904 I employed the plate-camera for this purpose in Alaska, but found that the labor necessary to plot the maps, even in a general way, was long and tedious. In 1905 a small Eastman panoramic camera was fitted with spirit-levels, a sightalidade and a transparent scale, introduced inside the camera to register the degree-points in the sky-line of the film-negative; also, arrows to indicate the horizon-line. This was, on the whole, successful; but the details in the topography were not brought out in the views with sufficient clearness, and the photographs were too small. These difficulties were overcome by obtaining a larger and more carefully constructed instrument, which was satisfactorily employed in the field during the year 1906. A panoramic view is made up of an integral number of perspective views upon flat surfaces, and logically is the most ac-

Jan 1, 1908

By CLARESCE CARLETON SEJIPLE

(Wilkes-Barre Meeting, June, 1911.) AT a number of mines in eastern Nicaragua, 3.5- and 5-ft. Huntington mills are used for grinding gold-ore after a preliminary breaking in jaw-crushers. The smaller mills are made sectional to facilitate transportation to the more difficultly accessible mines. The capacity of the smaller mills is about 20 or 25 per cent. that of the larger, but in proportion to the quantity of ore ground they require more power and are subject to greater wear. The notes herein given are from records of the performance of the larger mills, but, in general, apply to the smaller also. THE NATURE OF THE ORE. The ore occurred as a series of flat veins in a highly-decomposed rock, probably alaskite. The primary mineralization comprised pyrite, pyrrhotite, marcasite, chalcopyrite, and quartz; the oxidation-products of which were chiefly hydrated iron oxide or limonite, chrysocolla, azurite, and malachite. The kaolinization of the feldspar of the country resulted in the admixture of a great quantity of clay with the oxidized ore. The quartz was sandy, imbedded in the clay; and probably the greater part represented the residue from the crushed rock in the fissures after leaching, and kaolinization of the feldspar. There was little vein-quartz in the unaltered primary sulphide ore. Only the oxidized ore was mined for the gold that it contained in amounts that averaged $4 per ton. No specks of gold were ever seen in the ore, and the gold obtained by panning was always exceedingly fine. The amalgamation-bullion was about 800 fine in gold and 60 to 80 in silver. The ore delivered at the mill contained from 5 to 15 per cent. of moisture; during the rainy season the quantity was much greater. The moisture and clay made the ore so sticky that it had to be raked over steeply-inclined grizzlies; it hung in the ore-bins,

Oct 1, 1911

By G. C. Wallick, W. R. Foster, J. G. Savins

A comprehensive review of the salient features of the differentiation method of rheological analysis in Poiseuille flow from its inception circa 1928 is presented. Here no initial assumptions regarding the nature of the function relating rheological parameters to observed kinematical and dynamical parameters are required in the data-analysis process. In contrast, the integration method involves interpreting flow properties in terms of a particular ideal model. It is shown that, although both methods represent modes of solution of the same integral equation, being relatively bias-free, the differentiation method offers a more discriminating procedure for rheological analysis. The application to problems involving plane Poiseuille flow is also described. INTRODUCTION In most instances, the approach to the problem of interpreting the rheological properties of various compositions as they are affected by changes in chemical or physical environment, assaying the characteristics of a particular constituent of a suspension, analyzing flow behavior in terms of interactions between components in a system, to cite but a few examples, has been in terms of what Hersey1 terms the integration method. Briefly, it consists of interpreting flow properties in terms of a particular ideal model. The usual practice of the integration method is to choose a model with a minimum number of parameters because, other things being equal, it is desirable to use the simplest model which will describe the behavior of a real material and yet be mathematically tractable for the requirements of data analysis. This expression is then substituted into an equation which relates observed kinematical and dynamical quantities, such as volume flux Q and pressure gradient ], and angular velocity and torque T, in a capillary and concentric cylinder apparatus, respectively. The rheological parameters appear on integrating, in an expression relating the pairs of observable quantities such as those just given. In many instances a particular model provides a good representation of rheological behavior over a reasonable range of compositional and environmental changes. Just as often, however, it is obvious that the interpretation of rheological changes by the integration method is not providing realistic information about changes in flow behavior. A more general method of interpreting rheological data for a given material is to make no initial assumptions regarding the nature of the function relating rheological parameters to observed kinematical and dynamical quantities, e.g., flow rate and pressure drop in capillary flow or angular velocity and torque in a rotational viscometer. This general method Hersey1 terms the differentia-ation method. Instead of integrating, one differentiates the integral equation with respect to one of the limits, i.e., one of the boundary conditions; the resulting expression contains the same observable quantities just given, their derivatives, and the rheological function evaluated at that boundary. By obtaining these derivatives from experimental data, graphically or by a computer routine, they can be substituted into the differential equation and a graphical form of the function derived. THEORY OF THE DIFFERENTIATION METHOD FOR POISEUILLE-TYPE FLOWS In this introductory paper, two flow cases which are important in viscometry are considered (one for the first time) from the differentiation method of analysis, flow in a cylindrical tube and flow between fixed parallel surfaces of infinite extent, the basic integral equations being formulated in a manner analogous to the way they originally appeared in the literature. In addition, the following ideal conditions will be assumed: (1) an absence of anomalous wall effects, (2) isotropic behavior everywhere, and (3) steady laminar flow conditions. Before proceeding it would seem appropriate to preface the analysis of these flow geometries with the comment that the basic philosophy of the differentiation method could be said to stem directly from the efforts of Herzog and weissenberg2 to indicate systematically the various ways of using

By F. D. Rosi, C. A. Dube, B. H. Alexander

The slip and twinning planes have been determined in deformed crystalsof titanium by an X-ray method of analysis. The slip planes are of the type {1010} and {1011}, while the twinning planes are of the type {1072}, {1121}, and (1122). In the case of the predominant (1010) slip, a type I digonal axis of indices <1120> was the effective slip direction. Microscopic observations on the appearance of the three twin types disclosed a distinct difference in their shapes, and an attempt was made to correlate this difference with the amount of twinning shear. The slip mechanism was discussed on the basis of the difference in c/a ratios for the common hexagonal close-packed metals. IT is a general rule that slip in metals occurs most easily on the planes of greatest atomic density and of the largest interplanar spacing, and that the direction of slip is a close-packed direction. Thus, of the hexagonal close-packed metals which have been investigated by the German school in the decade 1925 to 1935 (cadmium, zinc, and magnesium), it has been found that slip occurs on the basal plane (0001) and in a <1120> direction.&apos; In the case of magnesium above 225oC, slip occurs on a first-order pyramidal plane (1011) as well as on the basal plane.&apos; The hexagonal metals, moreover, deform in part by twinning, and, again with the exception of magnesium at elevated temperatures, the twinning plane has always been reported to be a second-order pyramidal plane {1012).&apos; In view of this consistency in the plastic behavior of these metals, it has been supposed that the same slip and twinning elements would be operative in the other important hexagonal close-packed metals (titanium, zirconium, and beryllium), although there are some reasons why this may not be so. Referring to the tabulation in Table I of the axial ratios of the important metals in this structural class, it may be seen that they can be categorized into three distinct groups depending on the value of their c/a ratios. In the first group are cadmium and zinc with large positive deviations from the ideal ratio for closest packing. This expansion in the direction of the c-axis would be such as to accentuate the basal plane as the slip plane, because it increases the interplanar spacing. The second group includes cobalt and magnesium, which closely approximate the ideal ratio. In the third group are zirconium, titanium, and beryllium whose axial ratios are decidedly less than the ideal. The lattice of the elements in this group is compressed along the c-axis which, in effect, tends to make the basal plane less favorable for slip inasmuch as it reduces the interplanar spacing and the atomic density of this plane. Thus, for metals in the third group, it may be said that there is a certain indefiniteness about the glide plane, in that planes other than the basal plane may be expected to operate. The fact that magnesium begins to exhibit planes other than the normal slip and twinning planes at elevated temperatures may indicate that this behavior will become more pronounced in metals of lower axial ratios. For this reason it might be expected that the slip and twinning behavior of zirconium, titanium, and beryllium would be different from that found in cadmium and zinc. One indication that there is a difference is reflected in the recent work which has been done on the deformation textures of these metals."&apos; As will be shown later, there is a significant difference between the rolling textures of cadmium, zinc, and magnesium on the one hand, and zirconium, titanium, and beryllium on the other, and this difference suggests that the mechanism of plastic flow is not the same in these two groups of metals. From these considerations, therefore, it may be seen that there are good reasons why it cannot be concluded that titanium will have the same crystal-lographic elements of slip and twinning as those exhibited by zinc and cadmium. For the complete determination of these elements it would be most advantageous to have single crystals. However, much valuable information can be obtained by using coarse grained polycrystalline specimens, provided the grains are sufficiently large to permit X-ray

Jan 1, 1954