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By A. R. Ledoux

I was wondering whether we were going to adhere to our text. It seems to me that we are having a very remarkable meeting of mining engineers this year, because no matter what the texts may be that are assigned to us, we get back toward something higher; we turn to the consideration of questions of ethics, and of applied Christianity. Yesterday we listened to the most eloquent and remarkable address by Mr. Rickard in memory of Dr. Raymond, and it was told us that he was to speak about Raymond's achievements as an engineer. He did say considerable on that subject, but he was himself carried away with the spirit of the man and moved us all by his portrayal of Dr. Raymond's continued and fruitful labors for the betterment of mankind—that is to say, his religion. Our President asked me if I would say something this afternoon and I find in the bulbtin that the text of the discourses which we are to have here this afternoon is "Internlttional Cooperation in Mining in North America." But again I find that the eloquent speaker who has just preceded me has dwelt largely on ethical and spiritual cooperation rather than upon cooperation in mining. That is, cooperation as men, rather than solely as engineers. The imaginary line dividing Canada from the United States, unmarked by fort or military post, was mentioned by a previous speaker. There are going to be in the future, I am sure, fewer entanglements of the barbed wire of tariff discrimination along our border-—to that end let us cooperate. But there has always been a reciprocity in men. A Canadian conceived and created our great transcontinental line, the Great Northern Railway; an American made the Canadian Pacific what it is. In mining and metallurgy, American engineers, backed by American capital, have built up great Canadian industries while Canadian experts have developed some of the resources on this side of the line. They have done much more than develop our resources; some of them have been our leaders in sympathy for labor. It is therefore not a question of creating a spirit of cooperation, but of giving it freer scope and a fuller realization of fraternity—or, to use the word now more common and of deeper significance—brotherhood. These are days of combination. Corporate interests in this country are now compelled, or at least encouraged, to combine in ways that

Jan 1, 1920

By V. R. Garfias, R. V. Whetzel

It has been repeatedly questioned whether estimates of oil reserves are of any practical value, as the greater number of such calculations previously made have subsequently been proved to be grossly inaccurate. But even admitting partial justification for such statements, it must be evident that some idea, however approximate, of the available reserves of essential minerals—petroleum included—is of vital importance in mapping their development and the future trend of the related industries, particularly if it is kept constantly in mind that these estimates are not only never intended as a final word but must continually be subject to revision in accordance with the changes in their component factors. The value of these estimates, therefore, hinges on the clear understanding of what is meant by reserves and that the figures can only apply within the limited time when the controlling factors remain unchanged. It should be understood, further, that while estimates of possible and probable oil deposits are as a rule but idle conjectures, appraisals of proven oil reserves can undoubtedly be made with an ever-increasing degree of accuracy. And it is with this in mind that in the present study the endeavor has been to estimate only the world's proven oil reserves and to leave out of consideration the questionable volume of the probable and possible oil reserves. Such a survey presupposes further a clear distinction between the known amount of oil underground in proven fields at any one time, and the proven reserves: the portion that can be economically brought to the surface and made available for utilization. Only a fraction of the petroleum stored underground in proven fields— usually associated with natural gas—is or can be economically brought to the surface, and not all of the oik brought to the surface is economically utilized; also, although practically all the natural gas can be economically recovered and utilized, in actual practice a large part of the total volume that reaches the mouth of the well is wantonly blown into the air and wasted. It is thus estimated that in the United States only some 25 per cent of the petroleum stored underground in proven fields is actually brought to the surface; and in actual practice close to 25 per cent of the total gas produced is now absolutely wasted. And the dissipation of this

Jan 1, 1936

By Wallace Ralston

The East Texas district includes the northeast 38 counties of the State of Texas. It still remains one of the most important oil-and-gas-producing areas of the United States, since it includes within its boundaries the large East Texas field. Other fields of importance are: Van, Rodessa, Talco, Cayuga, Long Lake and Sulphur Bluff. Production is from the Nacatoch, Blossom, and Woodbine of the upper Cretaceous and the Paluxy and Glen Rose of the lower Cretaceous. Of these, the Woodbine is the most important, since it is the producing horizon iri the East Texas field. Fields East Texas Field.—There were 2471 oil wells, 1 gas well and 84 failures completed during the year of 1936 in the East Texas field; that is, 1565 fewer than in the year of 1935. The total number of producing wells is now 22,031, of which 50 are temporarily shut down; 18,435 wells flowing their production; 3150 pumping; 293 on gas-lift, and 82 operated by other methods. This shows an increase of 1642 wells on artificial lift over Jan. 1, 1935. The average daily salt-water production is estimated at 42,700 bbl. from 2327 wells—an increase of 1201 wells over the year of 1935. The field is now drilled to an average density of one well to 5.85 acres. Average bottom-hole pressure has dropped from 1193 Ib. to 1168 lb., approximately 1 lb. drop for each 6,600,000 bbl. of oil produced. During the month of December 1936, the estimated daily average production of illegal oil had dropped from 20,500 bbl. in December 1935 to 7500 bbl. The commercial gas production is of minor importance in the East Texas field, and figures for the amount of gas taken from the field are not available at the present time. Talco Field, Titus and Franklin Counties.—The discovery well was drilled by Housh, Thompson et al. on the C. M. Carr tract and completed in March 1936, as a pumping well making 552 bbl. per day of 24' gravity oil. This well was first completed at a total depth of 4208 ft., the top of the sand being 4190 ft. Later it was deepened to 4260 ft., which increased the production from 552 to 725 bbl. per day. This field is producing

Jan 1, 1937

By B. E. Lindsly

The withdrawal of gas and/or oil in appreciable quantity from a natural oil reservoir causes the pressure within the reservoir to diminish, and if the oil is completely saturated with gas, this dissolved gas begins to evolve from solution. The liberation of gas from solution in oil causes the oil to change in several ways, the principal changes being: (1) reduction in volume or "shrinkage"; (2) increase in specific gravity (decrease in degrees A.P.I.); (3) decrease of energy in the oil; (4) increased viscosity; (5) increased surface tension. As the writer's investigations have been concerned more with the first three items than with changes in viscosity and surface tension the following discussion relates particularly to the volumetric shrinkage of the oil, to the increased specific gravity, and to the decreased energy in the oil, each caused by the liberalion of dissolved gas. One of the most surprising facts that have developed in the study of high-pressure well-head and "bottom-hole" samples is the great reduction in volume that occurs in some oils when the naturally dissolved gas is liberated. High-pressure samples taken from well heads in the Oklahoma City, Kettleman Hills and Ventura, Calif., fields decreased in volume from 11.2 to 40.5 per cent when the dissolved gas was liberated in reducing the pressure on the sample to atmospheric. The amount of shrinkage an oil undergoes when gas is liberated depends upon the quantity of gas liberated and also upon its composition. A given volume of the heavier gases, propane and butane for example, will occupy more space in the oil than an equal volume of methane. The reason for this probably is that the molecules of the heavier gases are larger than those of the lighter gases. When gases are not in solution, and particularly when they are at low pressures, the distance between the gas molecules is so much greater than the dimensions of the molecules themselves that the mere size of the molecules has little effect upon the space occupied by the gas, Avogadro's hypothesis, which in effect states that all gases under the same conditions have the same number of molecules per unit volume, relates to this phenomenon. The fact that the heavier gases occupy more space than the lighter gases in the oil, and

Jan 1, 1934

By William Kent

ABOUT a year ago, the writer had occasion to assist Mr. John L. Gill, Jr., of the Pittsburgh. Car-wheel Works, in making a trial of his new testing machine. A piece of Bessemer steel, of about .34 carbon, was used as a test-piece, turned to a sectional area of one square inch for a length of five inches between shoulders, and pro¬vided with large round heads, which were fitted to what is called the " Wade grip." Measurements of elongation, accurate to , 1/10000 of an inch, were made by a special apparatus containing two micrometer screws, with electric contact attachment. The machine was operated by hand-power. Readings of elongation were taken at each increment of 2000 pounds stress per square inch, up to 44,000 pounds, the elongation corresponding to the latter figure being .0088 inch. The elongations up to this point remained almost exactly proportional to the stresses, the strain diagram, as shown on the Plate, from the origin to the point A, being a straight line (the deviation of no observation from the straight line being greater than .0002 inch). There being no indication of an approach to the elastic limit, the attendant at the hand-wheel and scale-beam was told to proceed as usual and move the poise forward 2000 pounds, or to 46,000, and turn the wheel until the beam was balanced. Noticing that the beam did not rise in the usual time, and that the elongation was increasing rapidly, the writer called to the attendant to stop turning the hand-wheel and to push the poise backwards until the scale-beam balanced. Instead of balancing at between 44,000 and 46,000 pounds, as was expected, it balanced at 40,000 pounds, and the elongation had increased to .0343 inch (or more than four times that recorded at 44,000 pounds), as plotted at the point B, the dotted line between A and B showing the supposed course of the strain diagram between these two points. Immediately upon recording the elongation the writer said to Mr. Gill, who was standing alongside: "This phenomena is without a parallel in my experience, and I know of but one way to account for it. The piece must actually be broken in its interior, through a flaw or weak portion of the metal. The test-piece is now equivalent to a tube, with

Jan 1, 1880

By William P. Mason

FoR reasons unnecessary to enter into here, I was called upon to contradict the statement that " closed metallic vessels, partly filled with water and heated, do not become shattered by violent explosion, but simply rupture by over-pressure;" and the following experimental results were obtained in support of my position : A piece of drawn brass tubing (telescope-tubing) 1 1/2 inches in diameter and 15 inches long was closed at both ends by screwing on heavy caps of bronze. Before closing the second end the vessel was half filled with river water, the cap was then screwed on, and the closed vessel was supported upon two iron anvils, and heated in the interval between the supports by a large Bunsen lamp. The resulting explosion (which was doe to over-pressure only and not to any more occult cause) was exceedingly violent. No small damage was done to the room in which the experiment was undertaken; and the noise was like that of a cannon. Those of the pieces which could be recovered are shown in Fig. 1. Upon examining the wreck, it was noticed that one of the heavy bronze end-caps had preserved its circular section and still contained that portion of the barrel of the tube which had been screwed into it, while the other end-cap contained no portion of the tube, and was moreover sprung into a shape more or less elliptical, as if from excessive lateral strain. It was also observed that the large pieces of the shattered boiler predominated towards the end which had been closed by the un-sprung end-cap. The reasonable explanation, in view of the facts, was, that over-pressure had caused the boiler to yield through the screw-threads at A B, Fig. 2, and the righthand end-cap had blown off, thus leaving the boiler half filled with water, greatly super-heated for the new (atmospheric) pressure to which it was suddenly reduced; that this water had consequently sprung instantly into steam with dynamite effect, shattering the tube and springing the remaining end-cap. The large pieces would be expected at the open end of the boiler, as at that point the "tamping "would have been that of the atmosphere only. This explanation assumes a rupture to have been caused by gradually increased pres-

Jan 1, 1893

ZAY JEFFRIES,* Cleveland, Ohio (written discussion?).-The microscope has, indeed, proved a mighty tool in the study of the structures of substances. It is limited in its resolving power to the wave length of the light used for illumination. A little in resolving power can be gained by using ultraviolet rays, which can only be detected by the photographic plate. Even the highest powered microscope only permits the study of aggregates of millions of atoms. The x-ray spectrometer, on the other hand, makes it possible to study the positions of the atoms in a crystal. The positions of the atoms in over fifty crystals have now been ascertained. But in amorphous substances the x-ray spectrometer is only able to tell us that the atoms seem to have no regular arrangement; the actual arrangement and method of grouping is still a mystery. In most perfectly formed crystals and in so-called "grains" in metals, the x-ray spectrometer teaches us that colloids seem to play no role inasmuch as the atoms are arranged in regular layers rather than in random clusters. In the boundary region between crystalline grains of like as well as unlike substances and in amorphous substances like glass, it seems probable that the random clusters, or colloids, play an important role. There still remains the application of wave lengths connecting the ultraviolet and x-rays both by direct reflection or diffraction and by the ultramicroscope. In the study of substances like glass, for example, it may be possible to identify the clusters or molecules by one wave length and to study the positions of the atoms in a cluster by using a smaller wave length. Any light that can be thrown on this important unknown subject and its relation to the properties of substances is therefore very welcome, and Mr. Alexander's paper is so written as to stimulate thought and experimentation in this direction. JEROME ALEXANDER (author's reply to discussion ?).-Col. Bancroft states' that in the case of alloys, the mass is always crystalline. While this generally may be so in the case of alloys, as ordinarily met with, before the alloy reaches this state or condition, its constituent particles must be in a still more finely dispersed state. In alloys, the speed' of transition between the finely dispersed state where the phases are amorphous, and the crystalline state where the phases are of known composi-

Jan 5, 1919

By Eugene Jablonski

Statistical data on the Polish producing business are available only for the first half of 1939. Because of the invasion of the country during September by Germany and Russia all sources of information have stopped, and it is impossible to get even an approximate picture of the status of the industry after that date. The long declining trend of Polish production, which was finally checked during 1938, kept a further upward tendency during the first half of 1939, and there is good reason to believe that the upward trend would have been maintained. It is true, there was little hope of reviving the slowly dying Boryslaw field, although there still remained a slight possibility for an extension in its southwestern direction. Repressuring plans were still discussed, but. could not be put into effect because of extremely complicated and split-up lease ownership. The Gorlice-Lipinki ficld continued to be the main factor in the increase of the country's production. During the first half of 1939 this field received a further important extension in a southern direction. The Schodnica field continued to use repressuring with success. At the end of June, 21 exploratory wells were drilling, 14 of which were within thc Carpathians and 7 in the Miocene geosyncline of the Carpathian Foreland. All of the wildcat wells drilled within the Carpathians were on the struct,ural cxtcnsion of old established fields, but part of the wildcats of the Foreland were on new geological and geophysical prospects. The Opary gas field of the Foreland discovered last year has been further developed. The Government-owned Polmin completed its third gasser. This well penetrated two sands; the upper one, 118 ft. thick, was found at 1312 ft., with an initial pressure of 570 lb. and capable of produeiring 10 million cu. ft. per day. The second sand, 91 ft. thick, was found at 1690 ft., yielding 20 million cu. ft., with a pressure of 760 lb. The well Mieczyslaw, drilled about 3 miles further north on the flank of the structurc, found the first sand watered. The Pioneer No. 5, at Chodonice near Przemysl, which reported somc gas last year, was 5696 ft. deep at the end of June, still drilling in Miocene. Anothe well in the same vicinity drilled by the Gasolina was 1708ft. deep.

Jan 1, 1940

By L. C. Morganroth

Discussion of the paper of L. C. MORGANROTH, presented at the New York meeting, February, 1916, and printed in Bulletin No. 110, February, 1916, pp. 475 to 481. DAVID B. REGER, Morgantown, W. Va.-I notice in the third paragraph of the first page of the paper, that in mentioning the clays of the Pottsville series, the author says: "The bed of clay found in the latter formation is unique in that flint clay is practically restricted to it. (A variety of flint clay is occasionally found in these upper deposits but this is in such small amounts as to be negligible."). If the author wishes to confine himself to the fire clays of Pennsylvania, as the title seems to indicate, I have nothing to say, but if he wishes to include a discussion on fire clays of the adjoining States which the. subsequent paragraphs of his paper seem to indicate, then I wish to call attention to the fact that there are large and extensive deposits of fire clay in the Allegheny series, immediately overlying the Pottsville in the northern counties of West Virginia. These fire clays have been studied carefully, and described in several reports of the West Virginia Geological Survey, first in the report on Ohio, Brooke, and Hancock Counties, in the northern part of the State; described later ,in the report on Monongalia, Marion, and Taylor Counties, and in the report on Preston County, which followed. In these latter counties (Monongalia, Marion, Taylor, and Preston) there are some beds of fine fire clay, varying in thickness from 6 to 10 or 12 ft., with a content of only 2 or 3 per cent. of fluxing ingredients, and these are of the typical Savage Mountain appearance and also have the typical Savage Mountain fracture. They have been prospected, but not mined a great deal. Several of them have been tested in blast furnaces and furnaces for other purposes, in glass-manufacturing plants, also for firebrick, arid have been found to be very good. They are simply awaiting development, and I merely want to call attention to the fact that there are plenty of them in the Allegheny series still above the Pottsville in West Virginia. There are two or three valuable seams which I have seen in person and have had analyzed in our laboratory.

Jan 5, 1916

By Ernest Gayford

This is a nontechnical paper on flotation, subdivided under three general headings: (I) Definition of flotation; (2) what flotation is now doing in Utah; and (3) what is the future of flotation? Definition T. A. Rickard defines flotation' as "the act or state of floating," from the French flottaison, water-line and flotter, to float. The dictionary defines flotation as "the science of floating bodies." The flotation process is a method of concentrating ores by frothing. Weinig and Palmer,2 define flotation as follows: What is the flotation process? Briefly, it consists in the agitation of finely divided ore in water containing bubbles of air or gas, a small amount of oil and, usually, other reagents, soluble and insoluble; under these conditions the small particles of native metals, sulfides, arsenides, antimonides, selenides and tellurides show a tendency to attach themselves to the films of the bubbles, and are thus carried to the surface of the water. The oxidized gangue minerals, such as quartz, feldspar, limestone, hematite, etc., show much less affinity for the bubbles, are easily wetted by the water, and either remain in suspension in the water, or sink to the bottom of the vessel. If the bubbles are sufficiently stable they can be removed, carrying their load of sulfide-mineral particles with them. Thus there can be effected a separation of the two classes of minerals from each other, assuming that the grinding has been sufficient to unlock all of the particles of different composition. The separation does not depend upon differences in specific gravity of the various minerals; in fact, the sulfides are usually heavier than the oxides, and some of the heaviest sulfide minerals are the easiest to float. A particle of mineral may be so large, however, that its weight will counteract its affinity for the film of the bubble. In most cases the ore must be fine enough to pass a screen having at least 48 meshes to the linear inch. Taggart3 defines flotation as follows: Flotation is a method of wet concentration of ores in which separation of mineral from gangue is effected by causing the mineral to float at or above the surface of a body of liquid pulp while the gangue becomes or remains submerged. The method

Jan 1, 1928

By G. F. Tagg

In an earlier paper1, the author described a method of interpreting earth-resistivity curves, based on the theoretical investigation of a single horizontal underlying stratum. If the four-electrode system of Wenner is employed, the resistivity in a homogeneous soil is given by the formula where a is the electrode separation and R is the resistance of the earth between the two inner electrodes. If the earth is not perfectly homogeneous, the application of this formula gives an apparent specific resistance varying with the electrode separation. In the special case of the single horizontal underlying stratum, there is a surface layer of thickness h and resistivity p1 and a lower layer, extending to infinity, of resistivity pz. It has been shown by Lancaster-Jones2 that the apparent resistivity obtained by an application of equation 1 is related to the true resistivities, the depth h and the electrode separation a by an expression of the formhere pa is the apparent resistivity and F is a function (actually an infinite series), of the ratio h/a, and a reflection coefficient k = (p2 — p1)/(p2 + p1). For given values of h/a and k, the right-hand side of equation 2 can be calculated, and curves drawn showing the relationship between pa/p1, h/a and k. Such a set of curves for the case when p1 > p2 is given in Fig. 1. When pl is less than pz it is more convenient to use conductivity instead of resistivity. Hence, if oa = the apparent conductivity = lip, and a1 = the conductivity of the upper layer = l/pl, it follows that GeophyGical prospecting by earth-resistivity methods is frequently applied to investigation of structural problems in geology. Fig. 1 indicates a scheme of the general arrangement used in these methods of measurements. The battery (or generator) E is connected with two "current electrodes" I1 and I2. The current of intensity J, supplied by this battery, passes through the earth between these elcc- trodes. A potential difference U will be measured between two other electrodes V1 and Vz, called "potential electrodes." According to the configuration of electrodes (Fig. I), the resistivity of a homogeneous soil results from the formula

Jan 1, 1940

By H. J. Struth

Economic law was accorded considerably more recognition by the oil industry last year than perhaps ever before. While proration was undoubtedly given added impetus in 1931, and the list of proponents of unit operation was noticeably lengthened, predominant evidence plainly shows that the functioning of economic laws dominated collective efforts to reduce the excessive above-ground supply of petroleum. Crude oil production was reduced more than 48,000,000 bbl. last year; imports from other parts of the world were substantially lower; stocks of crude were drawn upon to the extent of nearly 48,000,000 bbl.; domestic gasoline demand increased 2 per cent—and yet, prices of petroleum and its products were at the lowest levels in many years. To say that the ills of the oil industry during 1931 were due to the general depression that was felt in all other lines is tantamount to attaching an air of uncertainty to a group of commodities that have been proved to be an ever increasing necessity, even in times of depression. TO say that the potential productivity of proven oil-producing areas has been responsible for the unsatisfactory state of affairs last year, and now, is to admit failure to carry out the principles designed to control production in accordance with the limits prescribed by demand. In fact, there is no reason why a large proven potential supply of oil should not be considered a valuable asset to the industry; an assurance against future needs; a stabilizing influence in building up confidence in the ability of the industry to supply this and future generations with fuel and lubricant requirements at reasonable prices. At any rate, an assured future supply of oil should be interpreted to the public to mean that the oil industry is a legitimate, progressive industry, and not a group of prospectors madly searching for "liquid gold." There has been a great deal of romance connected with the history of the oil business—so much that the public has come to associate the word "oil" with untold riches. However, the financial statements of 1931 will furnish conclusive proof to the contrary. Too much oil, too many refineries, too many filling stations, too much capital invested; these and other "too muches" and "too manys" have perhaps been given more publicity than necessary. We seldom hear these

Jan 1, 1932

By Ernest Gayford

THIS is a nontechnical paper on flotation, subdivided under three general headings: (1) Definition of flotation; (2) what flotation is now doing in Utah; and (3) what is the future of flotation? . DEFINITION T. A. Rickard defines flotation1 as "the act or state of floating," from the French flottaison, water-line and fitter, to float. The dictionary defines flotation as "the science of floating bodies." The flotation process is a method of concentrating ores by frothing. Weinig and Palmer 2 define flotation as follows: What is the flotation process? Briefly, it consists in the agitation of finely divided ore in water containing bubbles of air or gas, a small amount of oil and, usually, other reagents, soluble and insoluble; under these conditions the small parti- cles of native metals, sulfides, arsenides, antimonides, selenides and tellurides show a tendency to attach themselves to the 6lms of the bubbles, and are thus carried to the surface of the water. The oxidized gangue minerals, such as quartz, feldspar, limestone, hematite, etc., show much less affinity for the bubbles, are easily wetted by the water, and either remain in suspension in the water, or sink to the bottom of the vessel. If the bubbles are sufficiently stable they can be removed, carrying their load of sulfide-mineral particles with them. Thus there can be effected a separation of the two classes of minerals from each other, assuming that the grinding has been sufficient to unlock all of the particles of different composition. The separation does not depend upon differences in specific gravity of the various minerals; in fact, the sulfides are usually heavier than the oxides, and some of the heaviest sulfide minerals are the easiest to float. A particle of mineral may be so large, however, that its weight will counteract its affinity for the film of the bubble. In most cases the ore must be fine enough to pass a screen having at least 48 meshes to the linear inch. Taggart defines flotation as follows : Flotation is a method of wet concentration of ores in which separation of mineral from gangue is effected by causing the mineral to float at or above the surface of a body of liquid pulp while the gangue becomes or remains submerged. The method

Jan 1, 1928

By S. D. Baumer, P. M. Hulme

B. M. Larsen (U. S. Steel Co., Kearny, N. J.)—Could we have some sort of an estimate on the cost of calcium carbide for this treatment? Also, if you used calcium carbide on carbon-saturated iron, would some effect hold back the reaction? P. M. Hulme (authors' reply)—As far as I know we have not worked on carbon-saturated iron. About 3½ pct C is the highest we have worked on. As far as cost goes, it depends on how much sulphur You have to take out. It will run anywhere from $0.75 to $2.00 a ton overall cost including the cost of carbide per ton of metal treated. That is, using the efficiencies that we show in this paper. We are getting better efficiencies now. T. L. Joseph (University of Minnesota, Minneapolis, Minn.)—Did you say 2 lb of calcium compound? Mr. Hulme—That is based on 10 lb of calcium carbide per lb of sulphur removed. D. E. Babcock (Republic Steel Corp., Youngstown, Ohio)—We have run this type of desulphurization process at the blast furnace. We have desulphurized between 100 and 200 at the blast furnace and taken the iron right out of the furnace with an injector system. The process gave us quite varied results; stratified iron, high sulphur on the top and low sulphur on the bottom, and we decided it was impractical. Mr. Hulme Just what was the type of injection equipment? Dr. Babcock—Nitrogen gas for one injection method and we used fairly large gun equipment. We followed the same general type of pattern you show only on a larger scale. Mr. Hulme—It sounds very much like what we call the gale of wind method. We have very erratic results with that. Dr. Babcock—We have tried several types, and particle sizes. The operation was not satisfactory. Mr. Hulme—Of course, we have never tried it on that scale except on a continuous basis. That is the reason we abandoned the idea of working on 35 ton ladles on a batch principle and took it as it came out of the cupola and treated it on the fly on a continuous basis. Dr. Babcock—When you compare the relative effectiveness of the process as carried out, it does not give a very favorable comparison of that process which is already developed. We did not feel it was worth the

Jan 1, 1952

By S. R. Elliott

The principles of the caving system, as they apply to mining soft iron-ore deposits, are well known, as this method has been in use for many years. It is, however, necessary to give a general description of it before describing the Athens method. The shaft and surface equipment should be placed at a sufficient distance from the orebody, so that the caving and pulling of the surface will not disturb the operations of the mine. Levels are started at the proper intervals, and when raises are completed, slicing commences at the top of the orebody and progresses downward. The necessary precautions are taken to avoid the occurrence of large open rooms and it is customary to break sufficient capping to form a mat to prevent heavy falls of ground from crushing through to the lower sublevels and endangering the lives of the workmen. Slicing is continued, and when sufficient width and length are undercut, the capping commences to cave, and in time a settlement occurs at the surface. As soon as this caving commences, the pressure on the timber increases; after it extends to the surface, the amount of pressure has a certain relation to the depth. In other words, the pressure increases with the depth, but not in direct proportion. At great depths, such as are found at the Athens, 2500 ft. (760 m.), the pressure might be so excessive that the cost of keeping working places open would be prohibitive. The actual caving of the surface in a deep mine, with a great thickness of capping, is slow and often takes years to accomplish. After sufficient width and depth have been undercut, the capping starts to break away, but, through arching, large masses of rock fill the opening, support the capping, and retard the continuation of caving. Caving to the surface is, therefore, retarded until either a sufficient thickness of the orebody is removed, or the width and length of the undercut part have been greatly increascd. I wish to emphasize this fact of slow caving, for it is on this principle that the success of the Athens system largely depends. Assuming that work is begun at the top, in this case at an elevation of about 1500 ft. (456 m.); that there is a thick bed of sand saturated with

Jan 1, 1922

By Rustum Roy, E. F. Osborn

THE investigation discussed in this paper concerns phase equilibria in the alumina-silica-water system. Studies in this system are part of a re¬search project sponsored by the Geophysics Branch of the Office of Naval Research2 directed toward increasing knowledge of the stability relations of metamorphic mineral assemblages. Inasmuch as metamorphic rocks consist largely of aluminosilicate struc¬tures, many of them hydrated, the system alumina-silica-water is a logical starting point for the systematic laboratory study of metamorphic mineral systems. Although logical, this is not, however, an easy approach to the problem because of the very great difficulty of obtaining transformations among structures in response to changes in temperature, pressure, and con¬centration. Commonly equilibrium among the phases in this system is exceed¬ingly difficult to attain. New laboratory techniques are required to produce certain structural rearrangements, such as inversion of diaspore to boehmite or the transformation of alumina-silica mixtures to andalusite or kyanite. Phase equilibrium data for the alumina-silica-water system are consequently only partly complete, and only a summary progress report is presented here. Crystalline phases in the alumina-silica-water system are numerous and many are common minerals. The oxide components exist as: quartz, tridymite, cristobalite, corundum, water, and ice. Binary compounds occurring naturally are: sillimanite, andalusite, kyanite, and mullite in the alumina-silica system and gibbsite, boehmite, and diaspore in the alumina-water system. The most abundant among the ternary compounds is the composition A12O3.2SiO2.¬2H2O, existing in the four structural modifications, kaolinite, nacrite, dickite, and halloysite. The hydrated form of halloysite, A12O3.2SiO2.4H2O, is here called endellite. Pyrophyllite, A12O3.4SiO2.H2O, is the third ternary compound of natural occurrence. In addition to these minerals, two other ternary crystalline phases have been encountered in this study. The first is a structure resembling montmorillonite and corresponding perhaps to the pure aluminian end member of the beidellite series. The other has a composition approximating A12O3.2SiO2.H2O but its composition and structure are still in doubt. LABORATORY PROCEDURE In these laboratory studies, a starting material such as an alumina-silica gel or one or more of the crystalline phases is wrapped in platinum foil,

Jan 1, 1952

By A. P. Anderson, J. H. Jensen, W. E. Breckoff

Bromine is the intermediate member of the halogen family of elements between iodine, a solid, and chlorine, a gas. The name is derived from the Greek "bromos," meaning stench. Bromine is the only nonmetallic element that is liquid at room temperatures with a melting point of -7.2° C and a boiling point of 58.78º C. Reddish brown in color, it dissolves easily in water to yield a red solution. Bromine volatilizes at ordinary temperatures to a red vapor that is very irritating to the eyes, nose, and throat. Density of the liquid is 3.12 and gas weighs 7.59 gpl at standard conditions. As the element is highly active, it exists in nature only as bromide compounds. Bromine was discovered by Antoine Jerome Balard in seawater bitterns in 1826 and first prepared in quantity in 1860. Distribution Bromine is widely distributed in nature and compounds occur in solution in natural brines, in seawater, saline lakes, oil and gas well brines, and in evaporite chloride minerals. The concentration of bromine salts ranges from 60-65 ppm in seawater to several thousand ppm in oil well brines and saline lakes. The distribution of bromine in marine evaporite minerals and in the solutions from which they crystallized was determined many years ago by H. E. Boeke (1908). Theoretical aspects regarding the geochemistry of bromine have been published in numerous papers (Raup and Mite, 1969). Bromine occurs in solid solution in carnallite and sylvite associated in potash deposits; in halite in salt beds; salt in oil shales; and in trona deposits. Its presence is useful as a guide in geochemical exploration. The analysis of small amounts of bromides in the presence of large amounts of chlorides is discussed by W. Schwerdtner (1963). Manganese, iron, and iodine may interfere with the determination. Other analytical methods are discussed at length in the literature (Stenger and Atchison, 1964). Sources and Reserves The sources and reserves of bromine, given in Table 1, appear ample to meet present and foreseeable requirements in all producing countries. With the occurrence of bromine salts in seawater and other brines, the potential for bromine production is worldwide. It has been estimated that 99% of all commercially recoverable bromine is in the ocean. However, actual subterranean brines having a higher bromine content than seawater will continue to be the preferred sources of bromine for the foreseeable future. [ ]

Jan 1, 1983

By B. D. Cullity

GOLD and beryllium form an intermediate phase composed of the two metals in equal atomic proportions and having the formula AuBe. According to Winkler,1 this phase probably exists in two modifications: beta, stable below about 600°C, and alpha, stable between 600°C and the melting point, about 740°C. Only the low- temperature beta form will be considered in this paper. EXPERIMENTAL PROCEDURE The gold used had a fineness of 999.75 to 999.85, balance mainly silver, and the beryllium purity was better than 99.8 pct. AuBe was prepared by melting the constituents in a beryllia crucible in an evacuated induction furnace. After melting and thorough mixing, the alloy was allowed to solidify in the crucible. No difficulty was encountered in obtaining a homogeneous ingot. Both chemical analysis and microscopic examination of the ingot showed that the alloy was essentially one phase, containing 50 at. pct gold. The alloy was quite brittle and powder samples could easily be pre- pared by grinding in an agate mortar. The X-ray diffraction patterns were made with CuK-alpha radiation in a Debye-Scherrer powder camera 57.3 mm in diameter. The film was placed unsymmetrically in the camera in order to afford a basis for am-shrinkage corrections. A sample homogenized at 5o0°C gave the same diffraction pattern as a sample taken from the as-melted ingot. GENERAL RESULTS The diffraction pattern of AuBe was readily indexed on the basis of a simple cubic lattice with ao = 4.659 ± 0.001kX. If the unit cell is assumed to contain four AuBe "molecules," the calculated X-ray density is 13.46 grams per cc as compared with the measured density of 13.55 gm per cc. The only missing reflections in the dsraction pattern are (100) and (220) (see Table I). Since these missing reflections are not those characteristic of body or face centering, the lattice of AuBe must be simple cubic. To locate the positions of the atoms within the unit cell, two possibilities had to be considered: I. The structure was disordered and there were eight positions to be filled by an "average" gold-beryllium atom. That the structure was disordered seemed unlikely since the lattice parameter did not vary with composition in alloys containing some- what more and somewhat less than 50 at. pct gold, indicating a fixed composition for AuBe.

Jan 1, 1947

By J. B. Austin

It is now well established, chiefly through the work of Davenport and Bain,' that the influence of temperature upon the rate of transformation of austenite to ferrite at constant temperature is represented by a curve of the type shown in Fig. 5 on page 295 and the reasons for this general shape have been discussed by them in a qualitative way. Thus, the upper part, or nose, of the curve is the resultant of two factors of which the rate of change with temperature is not the same, and by analogy with other like cases it is almost certain that these factors are: (1) the chemical potential, or driving force, of the transformation, which is zero at the equilibrium temperature and increases rapidly as the temperature falls below this point; and (2) a factor analogous to viscosity, or resistance of the crystal lattice to a change in structure, which also increases as the temperature is lowered. Just below the equilibrium temperature this virtual "viscosity" of the metal is relatively low—that is, the metal offers little resistance to a change in lattice—but the driving force is also small, and the net result is that the reaction proceeds slowly. As the temperature is lowered the magnitude of both factors increases; but at first the driving force increases more rapidly than the resistance and the reaction is observed to proceed more rapidly. At lower temperatures, however, the resistance begins to increase faster than the driving force, and eventually, at the nose of the curve, overbalances it, causing the reaction to proceed more and more slowly thereafter. This concept is somewhat, though not completely, analogous to that employed in certain electrical cases where the precise factors are known and are separately measurable. The current I (in amperes or coulombs per second) flowing through a given wire is proportional to the impressed potential, or driving force E, and is inversely proportional to the resistance R of the wire; that is, I = E/R. Stated in a slightly different way, the time required for one coulomb to pass a given point (1/I) is equal to R/E. If the temperature of the whole circuit is changed, the resultant change in 1/I will depend on the relative rates of change of R and of E,

Jan 1, 1935

By Theron Wasson

The state of Michigan showed considerable activity during 1935. The center of greatest interest was the Crystal field, which was unknown until March, 1935, and is an illustration of the effect of the unknown and unexpected on Michigan oil development. The fields of the state (Fig. 1) produced a total of 15,770,000 bbl. of oil in 1935, or about 5 million more than in 1934. In order to keep up this production 307 new oil wells were drilled, of which 88 were in the Crystal area, which produced 3,600,000 bbl. This field had a rapid development and reached its peak in October. Since that time increasing water encroachment has caused a rapid decline. The pay horizon at the top of the Monroe dolomite is only a few feet thick. Big producers were offset by dry holes or small wells. The discovery well, which was in section 11, Crystal township, Montcalm County, was drilled March 28, 1935. Its initial production was 5000 bbl. per day, and up to Dec. 31, 1935, had produced 350,000 bbl. of oil—dose to one-tenth of the total production of the field to that date. The Beaverton field, which was discovered at the close of 1934, did not develop rapidly. Four small producers were finished in the Dundee lime during the year. West Branch was active and at the end of the year had 97 producers, 72 of which were drilled during 1935. Most of the wells produce from the Dundee lime; a few are finished in the Traverse. The Birch Run field deserves special mention, for it is the one area where consistent production continues to be found in the Berea sand at about 1500 ft. Wells are small, 20 now producing a total of about 300 bbl. per day of oil of fine quality. The old Central Michigan producing area, extending from Nit,. Pleasant through Yost to Porter, continued to be the principal producing area of the state and accounted for 10,370,000 bbl. from 660 producing wells. Ninety-three new wells were drilled in this territory. The Porter field, at the southeast end of this producing trend, was outstanding from the standpoint of production. The old Leaton field of Isabella County added several new producers. Its production was greater than in 1934.

Jan 1, 1936