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By Paul H. Hunt

MANY MISUNDERSTANDINGS have arisen regarding -Al the purchase by the Government of 24,000,000 oz. of domestically produced silver annually for the next four years at a price of 64 1/2c. to the producer. Some editorials have an¬nounced rather sarcastically that be¬cause of the strong western silver bloc in Congress, the Administration is paying a bonus of approximately $22,000,000 to a few large silver produc¬ers of the West, the amount being figured on the total purchase of about 100,000,000 oz. and the difference between the Government price and the world price for silver. Actually the Government will make a profit on this purchase, due to seigniorage, of something over $60,000,000. The 96,000,000 oz. of silver, for which the producers will receive approximately $62,000,000, will be produced in association with at least $100,000,000 worth of lead, zinc, copper and gold; the greater part of this $162,000,000 worth of metal will be produced at little profit to the mining companies, as will be shown later, because of the low prices for lead, copper and zinc. This amount of money will be spent largely for labor and supplies, thus greatly relieving the national burden of unemployment. Certainly, western mining, in the purchase of this silver, is not victimizing the Federal Government.

Jan 1, 1934

By F. L. Rip, B. C. Haydon

Manganese silver ores are well known to be refractory toward cyanidation. Roasting and sulfurous acid pre-leaching have been suggested for improving their amenability. This paper describes the development and implementation of the sulfurous acid pre-leach process for retreatment of manganese silver tailings at Tonopah, Nevada. The history of the material is summarized and the mineralogy is described. A brief review of an earlier application of sulfurous acid pre-leaching of a manganese silver ore is presented.

Jan 1, 1985

By Frank J. Anderson

IN the cement region of the Lehigh Valley, a difference of 2 to 3 pct in CaCO3 can make or break a new quarry development, and experience of the Dragon Cement Co. has shown that values of calcium carbonate, as reported from churn drill samples, have been increased as much as 6 pct on the average when the same area was diamond drilled. This calcium carbonate increase consequently lowered the values for silica, iron, and alumina, and made these sections much more attractive. Since 1950, the Dragon Cement Co. Inc. has been engaged in extensive diamond drilling in the local limestone of the Northampton, Pa., region, known as the Jacksonburg formation, and in the Lebanon, Pa., region in the Annville limestone, both of Ordovician age.

Jan 12, 1954

By P. G. Winchell, M. Cohen, J. Woodilla

The kinetics of stabilization have been studied with respect to the isothermal component of the martensitic reaction in ivon-nickel alloys. Although the carbun (or nit-vogen) content may be very low in these alloys, it plays an important vole in the stabilization phenomenon. In fact, if these interstitial elements are removed by moist-hydrogen treatment, no evidence of stabilization is found. In the pvesence of 0.007 wt pct C, the activation energy for the stabilization process is comparable to that -for the diffusion of carbon (or nitrogen) in ferrite) rather than in austenitc. This suggests that the interstitial diffiision controlling the stabilization occurs within the martensitic embryos rather than in the matrix of the parent phase. The kinetics furthev indicate that the interstitial atoms tend to diffuse -from the embryos toward the suvroundings, thereby immobilizing the interface. This appears to be the origin of the stabilizing effect -found in these alloys. PHILIBERT' has shown recently that interstitial elements play an important role in the stabilization of martensitic transformations in iron-base alloys. However, determination of the temperature dependence for this stabilization process has produced values (- 11,000 cal per mol) that cannot be readily identified with the activation energy for diffusion of carbon (or nitrogen) in either ferrite or austenite. In the present work, the isothermal mode of the martensitic reaction was employed to derive the activation energy for stabilization, and this was found to agree fairly well with that for diffusion of carbon (or nitrogen) in ferrite. An iron-nickel alloy with 30.8 wt pct Ni and 0.007 wt pct C was used in these experiments, the specimens being in the form of rods 0.074 in. in diam and 2 1/2 in. long. The specimens were sealed in evacuated vycor tubes and austenitized at 1100°C for 1/2 hr prior to quenching in water. A second series of specimens was decarburized (and denitrogenized) prior to the above austenitizing treatment by annealing in moist hydrogen for 182 hr at 1215°C. In order to achieve a "standard" condition in the austenitic state, all the specimens were transformed to martensite by cooling to - 195°C before the final austenitizing. Both the 0.007 pct C and the decarburized series then had an Mi temperature of about - 30°C. The isothermal martensitic transformation was carried out at a reference temperature of -88"C, and was traced by means of electrical resistance measurements. Each resistance value was normalized by dividing by the resistance of the austenitic specimen at O°C, thus giving a resist- ance ratio R. The rate of decrease of the resistance ratio (-dR/dt) provided a measure of the transformation rate. It was found that a plot of R vs log t at the reference temperature resulted in a slightly curved line which could be closely approximated by two straight lines intersecting at a time of 10 min, as shown in Fig. 1. If G = dR/dlogt is the linear slope of either straight segment, the rate of transformation at any given time is: The ratio of G for 1 less than 10 min to that for t greater than 10 min was 1.19 for the 0.007 pct C series and 1.24 for the decarburized series. These ratios made it possible to compute the transformation rate at any time greater than 10 min, knowing the transformation kinetics prior to 10 min. The stabilization treatment was introduced by up-quenching from the reference temperature, usually after 10 min of isothermal transformation: to one of four stabilizing temperatures between 0" and 22"C. After holding for various times, the specimens were down-quenched to the reference temperature for additional isothermal transformation. In this way, it was possible to compare the transformation rate (- dR/dt), immediately after stabilization with the transformation rate (- dR/dt)U in the unstabilized condition. The degree of stabilization was defined as: Ordinarily, Gs and Gu would be measured after the same time of prim isothermal transformation.

Jan 1, 1960

By Richard L. Stowe

Four NX-diameter holes were diamond-drilled in competent granite. Samples of the recovered core were used in laboratory tests. A borehole, plate-bearing device known as a Goodman jack was used to perform load deformation tests on the rock in the core hole. The majority of samples used in the laboratory tests were taken from depths in the hole at or within 5 ft of those at which the plate bearing tests were made. Borehole camera records, compressional and shear wave velocities, and densities were measured. Dynamic elastic constants were computed for the in-situ material, while comparative data (except camera records) were obtained in the laboratory. These data were examined to evaluate the significance of the in-situ modulus of deformation (Ed), the value computed from Goodman jack tests. Average test results show an excellent correlation between in-situ and laboratory data. The ratio of laboratory to field deformation modulus ranges from 9.82 to 7.21 for 3,000 and 9,000-psi stress levels, respectively. The dynamic modulus ratio, ED field/Ep lab, is 1.02; the compressional wave velocity ratio, V8 field/V8 lab, is 0.94; the shear wave velocity ratio, V, field/V, lab, is 1.12; and the density ratio, field [y/y] lab, is 0.95.

Jan 1, 1973

By R. Schuhmann

D. W. Fuerstenau (Associate Professor of Metallurgy, Dept. of Mineral Technology, University of California, Berkeley, Calif.) In his excellent paper, Dr. Schuhmann has proposed a mechanism for conlrninution which can be utilized to explain a number of phenomena which have been observed in the size reduction of solids. The difference between the product obtained from a ball mill and from a rod mill can readily be explained by Dr. Schuhmann's hypothesis. Consider that the size distribution of the product from each comminution event is given by y; - 100 (x/ki) (1) where Yi is the cumulative percent finer than size x, ki is the size modulus, and is the distribution modulus for the single comminution event. The total product from a cornminution operation will be the summation of the products from all of the individual cornrninution events. If the size moduli from the various comminution events range from kl to kn , the size distribution of the total product will be a straight line on a log-log plot only to a particle size equal to k ,. Considering 100 volurnes of feed, the value of y for x equal to kl is Riven by where y is the cumulative percent finer than size kj, z is the number of comminution events of kind i, and vi is the volume of each particle crushed. y=z1 qv1+z2 qv2 (k1/k2) +.............zn qvn (k1/kn) (3) F or particle sizes greater than k1 7 e. 6. x = k3, the value of y will be given by k3 A y = z1 qv1 + z2bv2 + Z3uV3 + zn zn qvn (k3/kn)(4) Only when x is equal to k, will y equal 100. 'Thus, the total product from a comminution operation will be a straight line on a log-log plot strictly up to a particle size equal to kl and above that size the line will curve so that y will equal 100 for the coarsest particle or k, (see Fig. 1). The actual shape of the size of distribution curve will depend upon the relative number of conmninution events of different kinds. In the case of ball milling, the ratio kn/kl may be pite large and there will be considerable deviation at the coarse sizes in a Schuhmann plot. kIowever, the grinding action in a rod mill is such that fine particles are protected from the rods by the coarse particles. Consequently, kn/kl will be quite small and the product from a rod mill will give a straight line Schuhmann plot almost to y equal 100%. In his paper, Dr. Schuhmann also has presented a very straightforward definition of grindability derived from the basic energy equation E = Ak-a (5) where E is the energy required to comminute a material to a size modulus of k and A is a constant. According to Dr. Schuhmann, the grindability of a material is the volume of material comminuted finer than unit size per unit of energy expended, this being 1/A. For comparison of grindabilities at any size two numbers are required, both = and 1/A, and anyone tabulating grindabilities should give both of these numbers. Concerning the experimental determination of grindabilities, if the material being comminuted possesses distinct cleavage, the energy re quired for comminution is given by E = Ak-(a-y) (6) where y is small number less than = . Because of cleavage, less energy will be required for comminution. To be certain that cleavage does not affect the gindability of the material being tested, it is suggested that the method used by Dr. Charles for determining grindability be used to ascertain if the deviation exponent y is zero or finite. R. Schuhmann, Jr. (Author's Reply) Dr. Fuerstenau's interesting comparison of rod milling and ball milling

Jan 1, 1961

By Dilip K. Paul, Charles H. Jacoby

The economic importance of salt domes has been recognized throughout the world, primarily because of oil and gas accumulations on their flanks, and to a lesser degree, for the value of their salt and potash. Recently they have become of value as hosts for cavities used to store hydrocarbons. In the near future we believe that their main value will be a source of geothermal energy. Although tremendous effort has been expended on the understanding of the geology and physical characteristics of the strata intruded by salt domes, relatively little energy has been exerted in the comprehension of the salt dome itself. Salt domes have long been recognized as a geological heat anomaly. With respect to other sedimentary rocks, salt is a good conductor of heat. Expressing values in 10-3cgs units, sedimentary rocks vary from 1.0 to 8.0; metamorphic rocks from 5.2 to 8.4 and igneous rocks from 3.1 to 9.8. Rock salt in its pure form has a thermal conductivity of 17. Thus a salt dome can be expected to act as a conduit bringing heat vertically from deep within the earth's crust.

Jan 5, 1974

By Howard Martens, Pol Duwez

IN two papers published in 1949, alloys of chromium with the refractory metals tungsten, molybdenum, tantalum, and columbium were investigated in view of their possible use as high temperature resisting materials. For the Cr-Ta system, a partial phase diagram was presented and the only intermediate phase was identified at Ta2Cr3. A phase of the same composition was also observed in the Cb-Cr system. The X-ray diffraction data presented in these papers, however, were insufficient for crystal structure determination. It is shown in the present study that the only intermediate phase in both the Ta-Cr and the Cb-Cr systems corresponds to the ideal stoichiometric ratio TaCr2, or CbCr2. Both structures are cubic, MgCu, type. At high temperature, however, TaCr2 has a hexagonal MgZn, type structure, which can be retained at room temperature by fast cooling. The alloys were prepared by melting in a helium arc furnace on a water-cooled plate. The design of the furnace was essentially the same as that described in ref. 3. Some alloys were also obtained by sintering compacts made of the mixed powders pressed at 80,000 psi. The sintering was carried on for 4 hr at 1375°C. The tantalum and columbium powders were supplied by Fansteel Metallurgical Corp., North Chicago, 111. The tantalum powder was the reagent grade, with a particle size smaller than 400 mesh and a total impurity content less than 0.1 pct. The columbium powder was smaller than 325 mesh and contained approximately 0.1 pct C and traces of Fe, Ti, and Zr. The electrolytic chromium powder from Charles Hardy, Inc., New York, was smaller than 300 mesh and contained about 0.1 pct Na, 0.05 pct Ca, and traces of Cu, Al, Mg, Si, and Co. Powder diffraction patterns were obtained with a 14.32 cm camera, using copper Ka radiation filtered through nickel foil. The powder pattern of the TaCr2 alloy obtained by sintering at 1375'C was different from that obtained on the same alloy rapidly cooled from the melt. Contrary to this result, the powder pattern of CbCr2 was the same, whether the alloy was made by sintering at 1375°C or by melting, and was similar to that of the TaCr, sintered. It was also found that the structure of the TaCr2 specimen obtained by melting was retained after heating for 4 hr at 1590°C, but transformed into the structure found in the sintered specimen after heating for 4 hr at 1375°C. Hence, the structural change of TaCr2, appears to be a reversible polymorphic transformation. CbCr2 and ToCr2 Structure, Low Temperature Form By using large scale Hull-Davey charts, the powder pattern of CbCr, and of the low temperature form of TaCr2 were readily interpreted on the basis of a face-centered cubic lattice with a parameter of approximately 6.95 kX. The indices of the reflections together with the values of sin' 0 are given in Tables I and 11. From this list of observed reflections, it appears that the (200), (600), (024), (046), and (028) reflections are missing. The lack of (h00) reflections for h 4n indicates a four-fold screw axis. The missing (Okl) spectra for k + 1 An indicate the existence of a diamond glide d. The combination of these symmetry elements can be found in the O— Fd3m space group, which is therefore the most probable one. After having determined the approximate density of TaCr, by the immersion method, the number of molecules per unit cell was calculated and found to be nearly eight. This information, added to the fact that the most probable space group is O leads to the consideration of a structure of the MgCu2 type, in which the atoms have the following positions: 8 magnesium in a and 16 copper in d. On the basis of this structure, intensities were computed by means of the usual formula: 1 cos'20 I a sin2 cos where F is the structure factor; 8, the Bragg angle: and p, the multiplicity factor. As shown in Tables I

Jan 1, 1953

By F. D. George, M. J. Salkind

Al3Ni whisker-reinforced aluminum was found to exhibit good Charpy impact toughness and little notch sensitivity even though its room-temperature tensile elongation parallel to the whiskers is only 2 pct. This impact behavior was maintained d liquid nitrogen temperature (-196"C). It is postulated that this behavior is due primarily to the presence of the continuous aluminum matrix which provides sufficient 10calized ductility in the vicinity of the crack tip to absorb considerable energy from the advancing crack. The impact behavior of Al-Alni was found to be quite anisotropic. Of six orientations studied, the transverse orientation having the notch normal to the whisker axis was found to exhibit the lowest impact energy, whereas the transverse orientation having the notch parallel to the whisker axis was found to exhibit the highest impact energy. A significant differnce was noted between the impact behavior of material containing needlelike whiskers and that containing bladelike whiskers. Only two of the six orientations studied exhibited complete fracture for the material containing needlelike whiskers. On the other had, most of the specimens containing bladelike whiskers exhibited complete fracture. It was postulated that the bladelike whiskers block transverse flow, thus reducing the amount of plastic deformation ahead of the crack tip. One of the more significant advantages of composite materials is the prospect of combining high strength with toughness. In general, toughness is associated with materials which exhibit considerable ductility and can deform plastically in the presence of a stress concentration. Very strong materials which resist plastic deformation generally exhibit low toughness. At first glance, then, it would appear as though strength and toughness are mutually incompatible so that useful engineering materials would have to be a compromise between the two. One approach to the problem of combining the high intrinsic strength of ceramics with the toughness of metals was to mix them together to form a cermet. Unfortunately, the toughness of cermets was found to be rather disappointing. Whisker reinforcement of metals, however, appears to be a more promising approach. It has been demonstrated that whisker-reinforced metals produced by unidirectional solidification exhibit enhanced strength due to the presence of high strength nonmetallic whiskers. The total strain capacity of these composites in the direction of fiber alignment is limited to that of the fibers, the matrix being unable to carry the load once the fibers have failed. A characteristic, then, of whisker composites is low ductility in the direction of whisker alignment, on the order of a few percent elongation. This low elongation, which is usually associated with brittle behavior, should not be taken as an indication of low toughness. Such a material can exhibit significant ductility in directions other than parallel to the fibers7 and can therefore possess significant intrinsic toughness. Toughness in a fiber-reinforced metal is derived from several mechanisms. The first is due to the toughness of the matrix itself. A continuous ductile metal matrix can act as an effective crack arrest medium by undergoing localized plastic deformation. Cracks initiated from the surface of the composite or from a brittle fiber failure must travel through the matrix before reaching another brittle phase particle. A second crack arrest mechanism peculiar to fiber composites is due to the fact that, as a crack travels through the matrix and approaches a fiber, the plastic deformation ahead of the crack tip will result in loading of the fiber. This causes the matrix shear strength in the plastic zone to be apparently higher, thus extracting more energy from the crack and diverting the crack at an angle to the original direction of propagation. A third crack arrest mechanism occurs in fiber composites which exhibit a weak bond between fiber and matrix. The idea was proposed by Cook and Gordons that if a crack propagating transversely in a fiber composite were made to turn and run along the fibers by decohesion of the fiber-matrix bond, then toughness would be imparted by the blunting of the crack tip and the creation of new surfaces. The last mechanism, interfacial decohesion, is commonly noted in naturally occurring fiber composites such as wood, bone, and bamboo, and has been observed in man-made composites such as glass fiber-reinforced resins,g silica fiber-reinforced aluminum," laminated steel," and tungsten and silica fiber-reinforced electroplated copper.'' The first mechanism, crack arrest by plastic deformation in the matrix, has been noted in tungsten wire reinforced cast copper." The purpose of this investigation was to quantitatively assess the toughness of a whisker-reinforced metal as a function of orientation. Previous investigation considered only cracks propagating nominally perpendicular to the reinforcement. In this investigation, crack propagation in three mutually perpendicular directions as well as three intermediate orientations was investigated. The system chosen for study was the unidirectionally solidified A1-A13Ni eu-tectic alloy which has a microstructure consisting of 10 pct by volume of A13Ni whiskers in a matrix of aluminum This material exhibits two different kinds of whisker morphology, depending upon the rate at which it is solidified.' At low rates of solidification (less than 2 cm per hr) the whiskers are bladelike, whereas at higher rates of solidification they are

Jan 1, 1969

Eckley B. Coxe, Drifton, Pa.: Anthracite coal differs from other fuels in its greater solidity. It does not burn like coke or wood, or like bituminous and coking coals, which become more or less spongy when heated, so that combustion can take place to some

Jan 1, 1892

By WILFRED SYKES

THE story of the rolling of strip steel is not limited to any one plant or individual or group of individuals. It is a story with many ramifications. First of all, it should be understood that the strip mills we are considering are continuous mills, in that the steel passes directly from one mill to the other in a more or less straight line. Continuous mills are not new; in fact, they have been used for many years in the rolling of a few simple shapes. They were, however, driven by one motor through jackshafts, and as a result the speed of each roll stand had a fixed relation to that of every other stand in the series. This in turn fixed the reduction that could be made in each stand. The mill could produce simple things, but was not satisfactory for the production of the variety of strip now required. It was, therefore, necessary to get away from the restrictions of that kind of drive. To accomplish this, the designer could either separate

Jan 1, 1936

By J. Marvin Weller, M. King Hubbert

Preliminary investigations were undertaken with a Megger Ground Tester in 1931 by Hubbert to determine whether the faults in Hardin County, Illinois, could be located by earth-resistivity surveys. The results of these investigations, which were in part presented before this Institute in 1932,1 were sufficiently promising to warrant a more extensive field program in the same general area the following summer. During the second season an apparatus of the Gish-Rooney type was employed because of its greater sensitivity and to avoid the troublesome correction for resistance of potential electrodes necessitated by the use of a Megger instrument. The discussion of earth-resistivity traverses which constitute the main part of this paper is based entirely upon the results of the second season's work. All of the traverses were made with a constant electrode spacing of a equal to 100 ft., and the four-electrode technique was employed. Successive stations in these traverses were spaced at intervals of 100 ft. and the line of electrodes was carried parallel to the line of traverse. The graphs of resistivity profiles presented here (Figs. 1 to 3) are plotted with resistivities in ohm-centimeters as ordinates and with distance divided into stations at 100-ft. intervals as abscissas. After the traverses were run by Hubbert the results were computed, the profiles plotted, and tentative interpretations were made by him. These curves and interpretations were then taken into the field by Wellcr, who made a careful geological examination along the lines of traverse for the purpose of checking and supplementing Hubbert's interpretations. Weller then constructed a geologic cross-section extending along the line of each traverse. The accompanying diagrams graphically illustrate the correlation that can be made between earth resistivity and geology in this area.

Jan 1, 1934

By Ralph Wilcox

THE diamond drilling of certain characters of unstable rock forma-tion, as, for example, the copper-bearing schists of the Miami district in Arizona, is rendered most difficult by what is known as " caving" of the sides of the drill holes. As this caving is very greatly increased by the action of flowing water, it occurred to me, after experiencing a great deal of difficulty with caving in diamond-drill holes which I was drilling for the Miami Copper Co., that if I could substitute air for water, much of the caving-with resultant difficulties, such as decreased speed of sinking and increased consumption. of diamonds-would be overcome. After some experimenting, I found that it was perfectly practicable to substitute air for the water; forcing the air down the hollow rotating rods in the same manner as is done with water, the air passing out around the bit, which is thus cooled, and ascending on the outside of the rods to the collar of the hole, carrying the borings in just as satisfactory a manner as had been done by the water, but without the accompanying destruction or caving of the sides of the drill holes such as had been so generally experienced with the water. When water was encountered in the drilling this water was forced up to the collar just as it would have been had water been used in the .drilling, but with the correspondingly decreased flow there was relatively less washing or caving of the sides of the drill holes. The only change necessary in the arrangement of the drill is that a cross instead of a tee is used at the collar of the hole. A tightly woven jute bag is attached to one arm of the cross, for collecting and filtering the sample; and when drilling in dry ground a jet of water is attached to the opposite arm of the cross, to collect the dust and wash down the sample into the bag. The rods rotate through a stuffing box attached to the upper opening of the cross. The distention of the jute bag by the issuing air indicates the operating conditions as sufficiently as did the flow of water when using water in the drill hole.

Jan 10, 1913

By J. R. Schneider

INTRODUCTION Landowners in Texas for many years have freely granted, reserved and leased "oil, gas and other minerals" or interests therein. In recent years we have witnessed much litigation concerning what sub- stances should be included as "other minerals" within the phrase "oil, gas and other minerals," and this question has received the attention of numerous legal scholars. At the South Texas Uranium Seminar held in Corpus Christi, Texas, in September, 1978, Mr. William R. Dodson presented a paper dealing with this very subject and entitled "Uranium - Mineral or Surface? Who Owns It?" In his paper, Mr. Dodson reported on two recent Texas Supreme Court decisions, Acker v. a, 464 S.W.2d 348 (Tex. 1971) and Reed v. Wylie, 554 S.W.2d 169 (Tex. 1977). which held that the particular substance in question in each case is not a mineral within the phrase "oil, gas and other minerals" if substantial quantities of the substance lie so near the surface that production will entail the stripping away and substantial destruction of the surface. Since that time another chapter has been written in the Texas saga of "When is a Mineral not a Mineral?" and it is the intent of this paper to present an update of the Texas law. A review of the early Texas cases so ably covered by Mr. Dodson in his paper will not be repeated, except as is necessary to illustrate the evolution of the legal doc- trine which has been so aptly named "The Surface Destruction Test". BACKGROUND In order to appreciate the genesis of the problem, one must consider that oil and gas production commenced in Texas many years ago, Spindletop came in in 1901. As oil and gas became more valuable, land- owners with considerable frequency sold interest in the oil, gas and mineral estates in their lands, and reserved interest in the oil, gas and mineral estates in their lands when they disposed of their property. Due to the oil and gas background, and perhaps be- cause oil and gas was paramount in the minds of the parties, the traditional language employed in these grants and reservations was "oil, gas and other minerals" or variations thereof. There are literally hundreds of instruments employing this language constituting a link in the chains of title to thous- ands of acres of Texas land. In addition, there are thousands of acres of Texas land held by oil, gas and mineral leases, the primary terms of which have been perpetuated by production, containing similar language in their granting clauses. The severance of the mineral estate from the surface estate results in two separate and distinct estates, each having all of the incidents and attributes of an estate in land. with the surface estate being the serviant estate, and the mineral estate being the dominant estate and having certain easements in the surface estate to explore. produce and remove the minerals. Harris v. Currie. 176 S.W.2d 302, 305 (Tex. 1943). As observed by the court in the Harris case, this is because a grant or reservation of minerals would be wholly worthless if the grantee or reservor co~lld rwt enter upon the land in order to explore for and extract the minerals granted or reserved. Although the Texas law has recognized that an oil and gas lessee has the right to use so much of the surface as is reasonably necessary to produce the minerals. Warren Petroleum Corporation v. Monzingo, 304 S.W.2d 362, 363 (Tex. 1957), recent decisions of the Court have qualified this doctrine. In Getty Oil Company v. Jones. 470 S.W.2d 618 (Tex. 1971). Getty's pumpine, units were interfering with ones self-propelled sprinkler system utilized for irrigating the premises, and Jones sought to require Getty to install the-pumping units in cellars so that the sprinkler system could pass over them. In an effort to accommodate both the surface estate and the mineral estate, the court held (page 622) "...where there is an existing use by the surface owner which would otherwise be precluded or impaired, and where under the established practices in the industry there are alternatives available to the lessee whereby the minerals can be recovered, the rules of reasonable usage of the surface may require the adoption of an alternative by the lessee". Bearing in mind that the "reasonable use doctrine" grew up in the oil and gas industry involving sub- stances which can be produced by methods that do not destroy or deplete the surface estate, the question presented is whether the Texas courts will extend this doctrine to situations where claimants of "other minerals" seek to produce shallow deposits of iron ore, coal, lignite and uranium by surface mining methods which do destroy or deplete the surface estate? The surface destruction test has answered this question in the negative, at least as to iron. coal and lignite. However, the multitude of mineral estates in Texas which have been created by a grant. reservation or lease of "oil, gas and other minerals" will, doubtlessly, continue to fuel the fires of litigation. EARLY TEXAS DECISIONS In view of the evolution of the Surface Destruc- tion Test, an exhaustive review of the early Texas

Jan 1, 1980

By R. A. Vandermeer, J. C. Ogle

Two distinct types of depth-dependent variations in texture have been observed in niobium cold-rolled various amounts up to 99.5 pct reduction in thickness. These nonuniformities are thought to be the results of nonhomogeneous plastic dewmation during rolling. The first type is characterized by a zone at intermediate depths that tends to lack certain strong orientations which are present in the surface and center layers of the rolled stock. This type of texture modification seemed to be associuted with "high" body rolling and may be related to the shape of the zone of deformation in rolling. The second type of texture inhomogeneity found involved the formation of a unique texture in the surface layers of heavily rolled strip. High fiiction forces between work piece and rolls appear to be needed to generate and maintain this texture. We believe that this unique surface texture results from a shear mode of deformation in the surface layers. THE evolution of texture in both the surface and center regions of cold-rolled niobium as a function of increasing deformation from 43 to 99.5 pct reduction in thickness was reported in a previous paper.' It was noted that for strips rolled between 95 and 98 pct reduction a distinctly different texture appeared in the surface layers which was unlike the center texture. Certain other layer to layer textural variations were also detected during the experimental phase of that work but were not described in the paper. Surface textures have been reported previously for the bcc materials iron and Steel2-4 and are well known in the fcc metals.5 It is usually stated that these are shear textures which arise under conditions of high friction between specimen and rolls. Work by Mayer-Rosa and Haessner5 n niobium rolled under conditions presumed to be high roll friction gave no indication, however, of a surface texture in that material. This is indeed puzzling in view of our results.' Thus we undertook additional experiments designed to study the stability of the surface texture for certain rolling variables. The variables investigated were the presence or absence of lubrication, amount of reduction per pass, and reverse vs unidirectional rolling. It is the purpose of the present paper to describe the kinds of depth-dependent textural inhomogeneities that we have observed in rolled niobium as well as to present the results of our recent experiments on the stability of the surface texture. Possible explanations for the depth-dependent texture variations will be discussed in terms of nonhomogeneous plastic deformation during rolling. EXPERIMENTAL Specimens cut from the niobium rolled to different reductions in the previous study1 were examined at various layer levels throughout the strip thickness for textural inhomogeneity. The specimen surfaces were either etched or machine ground and etched to remove material to a specific depth. Textures were determined by means of the Schulz X-ray reflection pole figure method with a Siemens texture goniometer and Cum X radiation. Since the important intensity peaks of the textures in niobium are usually located on the normal direction (N.D.) to rolling direction (R.D.) radius of the (110) pole figures, it was sufficient in many cases to scan only along this radius. At selected depths or where additional information was required the entire (110) pole figure was also obtained. In studying the stability and formation of the surface texture, experiments were conducted on 0.400-in.-thick, fine-grained, randomly oriented niobium specimens extracted from the same starting stock as that used in the earlier study.' Two of these specimens were rolled at room temperature to a total reduction of 96.4 pct. One was rolled between cleaned and degreased rolls with no lubrication. The other was lubricated between passes with Welch Duo Seal vacuum pump oil. The rolling schedules of each were kept as nearly identical as possible. Drafts were of the order of 0.006 to 0.012 in. per pass. Other experiments consisted of rolling specimens at constant fractional reduction per pass, i.e., (ta- tb)/ta equals a constant where ta and tb are the entrance and exit thickness of the rolled stock, rather than at a constant draft, i.e., ta- tb equals a constant. Ten specimens were rolled at room temperature on a two-high, motor-driven rolling mill with 8-in.-diam rolls. These specimens were rolled to thicknesses of between 0.041 and 0.073 in. (82 to 90 pct total reduction) at approximately constant reductions per pass ranging from 9 to 45 pct. Kerosene was used as a lubricant. Half of the specimens were always rolled in the same direction while the other half were reversed end to end at each pass. The texture in the surface regions was determined with the X-ray technique described above. RESULTS The textural inhomogeneities noted in niobium rolled from fine-grained, randomly oriented stock 1.5 in. long by 0.75 in. wide by 0.40 in. thick can be classified into two types. The first may be discussed with the aid of Figs. 1 to 3. Fig. 1 is a three-dimensional plot of the X-ray intensity in units of times random vs f , the angle from the N.D. to any point along the N.D. to R.D. radius of the (110) pole figure, and depth, given as percent of the thickness (?t/to X 100, where at is the thickness of material removed and to is the as-rolled

Jan 1, 1970

By H. T. Bowman

For more than 80 years the Bessemer process has depended upon the ability, skill, and judgment of the blower, although as early as the I860's it was recognized that the process would benefit by some type of instrumental contro1.l IIowever, instruments with sufficient recording speeds did not exist, so the end-point determination was always dependent upon the blower's eye. This placed an obstacle in the way of precise experimental work, because of the absence of the necessary records and reference points as reported by Work.2 The use of the photocell provided the instantaneous record of the blow that made this experimental work possible and provided more scientific control for the process as discussed by Graham,3 A brief description of the progress of the blow will illustrate the recording function of the instrument. The silicon in the iron is being oxidized during the first minutes of the blow, as pointed out by Henning4 in a table showing the order of metalloid elimination. The product of this oxidation is a solid that remains in the converter, so there is virtually no flame during this part of the blow. This low flame luminosity is illustrated by the flame recording shown in Fig. I, where the silicon blow is plainly marked. The dull flame of the silicon blow gradually gives way to the brilliant carbon flame as the increasing quantities of carbon monoxide formed inside the converter burn to dioxide upon contact with the atmosphere above the vessel. When the carbon reaches some low value under 0.20 per cent, there is insufficient menoxide formed to maintain the dioxide flame, so its intensity drops. Throughout the flame drop carbon continues to burn, until at some value around 0.05 per cent an arrest occurs in the recorded drop. This point has been designated as the end point. The period of time from this end point until the vessel is turned upon its side and blowing has stopped has been called the afterblow. This afterblow is used as a measure of the degree of metal oxidation, and uniformity demands that it be controlled within narrow limits. Iron and blowing conditions are likely to change several times during a turn, necessitating corresponding changes in end-point control. It is the purpose of this paper to discuss these changes, the factors that make them necessary, and their bearing upon the quality of steel. Carbon-FeO Relationship In the Bessemer process oxidation relationships are precise. Fig. 2 shows a graph of the carbon-FeO relationship. The familiar "bomb-test" method, described by Mccutcheon and Rautio,5 was used for obtaining these and all other dissolved FeO values herein reported, all tests being taken from the converter before deoxidation unless otherwise noted. All tests of 0.10 per. cent carbon and above were obtained from metal blown for duplexing. McGinley and Woodworth6 reported iron oxide values for blown metal, but their tests were obtained by a . different method than were those

Jan 1, 1942

By H. T. Bowman

For more than 80 years the Bessemer process has depended upon the ability, skill, and judgment of the blower, although as early as the I860's it was recognized that the process would benefit by some type of instrumental contro1.l IIowever, instruments with sufficient recording speeds did not exist, so the end-point determination was always dependent upon the blower's eye. This placed an obstacle in the way of precise experimental work, because of the absence of the necessary records and reference points as reported by Work.2 The use of the photocell provided the instantaneous record of the blow that made this experimental work possible and provided more scientific control for the process as discussed by Graham,3 A brief description of the progress of the blow will illustrate the recording function of the instrument. The silicon in the iron is being oxidized during the first minutes of the blow, as pointed out by Henning4 in a table showing the order of metalloid elimination. The product of this oxidation is a solid that remains in the converter, so there is virtually no flame during this part of the blow. This low flame luminosity is illustrated by the flame recording shown in Fig. I, where the silicon blow is plainly marked. The dull flame of the silicon blow gradually gives way to the brilliant carbon flame as the increasing quantities of carbon monoxide formed inside the converter burn to dioxide upon contact with the atmosphere above the vessel. When the carbon reaches some low value under 0.20 per cent, there is insufficient menoxide formed to maintain the dioxide flame, so its intensity drops. Throughout the flame drop carbon continues to burn, until at some value around 0.05 per cent an arrest occurs in the recorded drop. This point has been designated as the end point. The period of time from this end point until the vessel is turned upon its side and blowing has stopped has been called the afterblow. This afterblow is used as a measure of the degree of metal oxidation, and uniformity demands that it be controlled within narrow limits. Iron and blowing conditions are likely to change several times during a turn, necessitating corresponding changes in end-point control. It is the purpose of this paper to discuss these changes, the factors that make them necessary, and their bearing upon the quality of steel. Carbon-FeO Relationship In the Bessemer process oxidation relationships are precise. Fig. 2 shows a graph of the carbon-FeO relationship. The familiar "bomb-test" method, described by Mccutcheon and Rautio,5 was used for obtaining these and all other dissolved FeO values herein reported, all tests being taken from the converter before deoxidation unless otherwise noted. All tests of 0.10 per. cent carbon and above were obtained from metal blown for duplexing. McGinley and Woodworth6 reported iron oxide values for blown metal, but their tests were obtained by a . different method than were those

Jan 1, 1942

By Gerhard Derge, Arthur H. Grobe, Harold Markus

The high corrosion resistance possessed by tin under most circumstances, combined with its generally satisfactory appearance and useful physical properties, has led to many and varied uses for the metal. These uses have been partly limited by the fact that tin is an expensive metal, therefore many applications have been developed in which tin has been employed in combination with lead, either by coating, as in tin-lined collapsible tubes, or by the formation of alloys containing various proportions of tin-rich and lead-rich phases, as tcrne plate. A detailed knowledge of the corrosion characteristics of the tin-lead couple therefore is of general interest and has become specially important at the present time, when every effort is being made to conserve tin as much as possible. The present study has been limited to carbonate solutions with a pH range from 8.4 to 11.2 so that the results may be related to earlier work on the corrosion of tin and its alloys. 1-3,6 In these papers, the effects of a number of anion and cation additions to these solutions have been observed. Apparatus and Method The electrodes for the corrosion cell were cut from rolled sheet about 1/16 in. thick. The length of all specimens was held constant at 7 in., while the width was varied from M to 2 in. These electrodes were fastened to brass electrode supports, which were attached to rubber stoppers fitting into tall-type one-liter Pyrex beakers that contained the electrolyte. The lead electrodes were prepared from Omaha pig* and the tin was rolled from a slab of Chempur.† After cutting to size, the sheets were polished with No. I emery paper and cleaned with carbon tetrachloride. The edges, back and upper parts of the specimen were coated with a synthetic lacquer, which was supplemented with beeswax for the lead electrodes. The binding posts were coated with beeswax after the electrodes had been clamped. The pH of the electrolyte was controlled by adjusting the ratio of carbonate to bicarbonate. Approximately 600 ml. of electrolyte was used in each beaker. The entire assembly was placed in an oil bath thermostatically adjusted to operate at 30°C. + 0.1". Potentials were measured against a saturated calomel electrode connected to the cell by an agar-agar salt bridge. The carbonate solution used in the salt bridge was the same as that used in the corrosion cell. Currents were measured with a milliam-

Jan 1, 1942

By Harold Markus, Arthur H. Grobe, Gerhard Derge

The high corrosion resistance possessed by tin under most circumstances, combined with its generally satisfactory appearance and useful physical properties, has led to many and varied uses for the metal. These uses have been partly limited by the fact that tin is an expensive metal, therefore many applications have been developed in which tin has been employed in combination with lead, either by coating, as in tin-lined collapsible tubes, or by the formation of alloys containing various proportions of tin-rich and lead-rich phases, as tcrne plate. A detailed knowledge of the corrosion characteristics of the tin-lead couple therefore is of general interest and has become specially important at the present time, when every effort is being made to conserve tin as much as possible. The present study has been limited to carbonate solutions with a pH range from 8.4 to 11.2 so that the results may be related to earlier work on the corrosion of tin and its alloys. 1-3,6 In these papers, the effects of a number of anion and cation additions to these solutions have been observed. Apparatus and Method The electrodes for the corrosion cell were cut from rolled sheet about 1/16 in. thick. The length of all specimens was held constant at 7 in., while the width was varied from M to 2 in. These electrodes were fastened to brass electrode supports, which were attached to rubber stoppers fitting into tall-type one-liter Pyrex beakers that contained the electrolyte. The lead electrodes were prepared from Omaha pig* and the tin was rolled from a slab of Chempur.† After cutting to size, the sheets were polished with No. I emery paper and cleaned with carbon tetrachloride. The edges, back and upper parts of the specimen were coated with a synthetic lacquer, which was supplemented with beeswax for the lead electrodes. The binding posts were coated with beeswax after the electrodes had been clamped. The pH of the electrolyte was controlled by adjusting the ratio of carbonate to bicarbonate. Approximately 600 ml. of electrolyte was used in each beaker. The entire assembly was placed in an oil bath thermostatically adjusted to operate at 30°C. + 0.1". Potentials were measured against a saturated calomel electrode connected to the cell by an agar-agar salt bridge. The carbonate solution used in the salt bridge was the same as that used in the corrosion cell. Currents were measured with a milliam-

Jan 1, 1942

By Robert C. Berggan

The hot-milling process for reconditioning rock-drill bits is not new. It has been employed by a few mines for years and in the past decade it has been widely adopted, as its advantages have become better known. Because of the extensive commercial development in England and Canada of machines to operate on this principle, general acceptance has been largely in the British possessions and until recently has been chiefly in the field of conventional steel. In the past two years there has been a definite trend toward hot-milling of detachable bits in Canada, but only in the past year has any considerable attempt been made to build special machines for this type of work. Generally a machine designed for conventional steel has been used and special holders employed to manipulate the bit. As early as 1934 at least one operator in the United States had adapted hot-milling to conventional steel with a substantial saving in resharpening costs.1 Several other operators have taken it up but there has been no widespread adoption of the method in this country by users of conventional steel. This may be partly explained by the fact that until recently no American manufacturer produced this equipment and operators have been obliged to build their own hot-millers or import them. Several years ago a few machines were built in Seattle, Washington, and operated in some mines in the northwest, but, for reasons not generally known, the effort was abandoned. The Process Hot-milling performs the function of re-dressing the bit at a forging temperature of about 1650°F., by the removal of metal from the flutes with a milling cutter, followed by a similar cut from the bit gauge. Conventional bits are thus treated following the usual forging operation in a sharpener, and usually in the same heat.

Jan 1, 1940