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By Jay R. Burns

TWO magnesium sand-casting alloys are commonly favored in the United States. These are referred to as H and C alloys (Dow Chemical Co.) or 4Mz65 and AM260 alloys (American Magnesium Corporation). Both are of an aluminum-zinc-manganese type. H alloy contains 6 per cent aluminum and 3 per cent zinc and is characterized by relatively good toughness. C alloy contains 9 per cent aluminum and 2 per cent zinc and is employed where high yield strength and pressure tightness are required. Examination of magnesium castings poured in Europe and England,'J however, demonstrates that H and C alloys are replaced by .%8 and AZ~I, respectively. That is, A8 reprcsents a magnesiurn alloy having superior toughness while A291 is suitable for high yield strength and pressure-tight applications. The basic difference between the .Ameri-can and European alloys is that the foreign alloys employ a somewhat higher aluminum content and less zinc than is found in H and C alloys. The mechanical properties of the alloys, when divided into high and low-aluminum groups, are quite similar, as determined from separately cast foundry-control type test bars ,In this paper the decrease of mechanical properties caused by any given amount of microporosity is measured for H, C, A8, and AZ~I alloys. The relative susceptibility of each of the four alloys to microporosity is also determined. Typical mechanical properties and nominal chemical analyses are reported in Table I. The apparent similarities between the two alloys in each group have led to considerable discussion as to the relative merits of each of the compositions.2 Popular points for comparison between the alloys have been the relative susceptibility of each of the four alloys to microporosity6 and the effect of this microporosity on their mechanical properties. It is primarily intended, in this paper, to show the

Jan 1, 1946

By Jay R. Burns

TWO magnesium sand-casting alloys are commonly favored in the United States. These are referred to as H and C alloys (Dow Chemical Co.) or 4Mz65 and AM260 alloys (American Magnesium Corporation). Both are of an aluminum-zinc-manganese type. H alloy contains 6 per cent aluminum and 3 per cent zinc and is characterized by relatively good toughness. C alloy contains 9 per cent aluminum and 2 per cent zinc and is employed where high yield strength and pressure tightness are required. Examination of magnesium castings poured in Europe and England,'J however, demonstrates that H and C alloys are replaced by .%8 and AZ~I, respectively. That is, A8 reprcsents a magnesiurn alloy having superior toughness while A291 is suitable for high yield strength and pressure-tight applications. The basic difference between the .Ameri-can and European alloys is that the foreign alloys employ a somewhat higher aluminum content and less zinc than is found in H and C alloys. The mechanical properties of the alloys, when divided into high and low-aluminum groups, are quite similar, as determined from separately cast foundry-control type test bars ,In this paper the decrease of mechanical properties caused by any given amount of microporosity is measured for H, C, A8, and AZ~I alloys. The relative susceptibility of each of the four alloys to microporosity is also determined. Typical mechanical properties and nominal chemical analyses are reported in Table I. The apparent similarities between the two alloys in each group have led to considerable discussion as to the relative merits of each of the compositions.2 Popular points for comparison between the alloys have been the relative susceptibility of each of the four alloys to microporosity6 and the effect of this microporosity on their mechanical properties. It is primarily intended, in this paper, to show the

Jan 1, 1946

By Jay R. Burns

Two magnesium sand-casting alloys are commonly favored in the United States. These are referred to as H and C alloys (Dow Chemical Co.) or AM265 and AM260 alloys (American Magnesium Corporation). Both are of an aluminum-zinc-manganese type. H alloy contains 6 per cent aluminum and 3 per cent zinc and is characterized by relatively good toughness. C alloy contains g per cent aluminum and 2 per cent zinc and is employed where high yield strength and pressure tightness are required. Examination of magnesium castings poured in Europe and England,1,2 however, demonstrates that H and C alloys are replaced by A8 and AZ91, respectively. That is, A8 represents a magnesium alloy having superior toughness while AZ91 is suitable for high yield strength and pressure-tight applications. The basic difference between the American and European alloys is that the foreign alloys employ a somewhat higher aluminum content and less zinc than is found in H and C alloys. The mechanical properties of the alloys, when divided into high and low-aluminum groups, are quite similar, as determined from separately cast foundry-control type test bars.3 In this paper the decrease of mechanical properties caused by any given amount of microporosity is measured for H, C, A8, and AZ91 alloys. The relative susceptibility of each of the four alloys to microporosity is also determined. Typical mechanical properties and nominal chemical analyses are reported in Table I. [ ] The apparent similarities between the two alloys in each group have led to considerable discussion as to the relative merits of each of the compositions.2 Popular points for comparison between the alloys have been the relative susceptibility of each of the four alloys to microporosity5 and the effect of this microporosity on their mechanical properties. It is primarily intended, in this paper, to show the

Jan 1, 1946

By Owen Thornton

Recently equations have been presented by Rose and Bruce' and by Rose², showing how the relative permeability of a reservoir rock may be determined from the capillary character of the rock. In particular, equations were developed to show the relationship between capillary pressure and the effective permeability to the wetting phase in a poly-phase flow system. The equations are as follows (nomenclature the same as in the Rose and Bruce paper) Rose and Bruce assume that the average length of path (L,), which the wetting fluid follows in flowing through a porous media is independent of the saturation to the wetting phase, so that 1 is a constant dependent only on the k rock, and the permeability to the wetting phase is a function of the saturation and of the capillnry pressure: In measuring the flow of ekctric current through partially saturated core samples, it has been observed that the electrical resistance usually is not a simple linear function of saturation. This fact indicates that the average length of path in the flow of electric current is not independent of saturation, but rather that the tortuosity of the path depends upon the average saturation to the conducting fluid as well as upon the characteristics of the rock. itself. Inasmuch as the flow of fluid and the flow of electric current in many respects are analogous, it may be indicated further that the length of path for fluid also may not be independent of saturation. The following relationship can be derived to express the resistance to flow of electric current through a core sample partially saturated with conductive wetting phase, the non-wetting phase being non-conductive: where L is the average length of path followed by the current in flowing through a length L of partially saturated core, where L is the length of current path when the core is fully saturated, and where Rs and R, are the specific resistivities of the partially saturated and saturated core sample, respectively. It will be noted that R., the specific resistivity of the core sample when S, = 1.0, is equal to the "formation resistivity factor"' multiplied by the specific resistivity of the saturating fluid. If it be assumed that the average lengths of path for fluid flow and for the flow of electric current are the same, then equation (5) may be combined with equations (l), (2) and (3) to give the following relationship: The above equation suggests including a correction for tortuosity when calculating the relative permeability of a reservoir rock to a wetting phase. The correction factor may be obtained from the resistivity-saturation relationship. For instance, the following calcu- lations are obtained for the unconsoli-dated sands described by Leverett Kw Kw Sw R°/Rs Pt/Pc¹ (Calc.) (Obs.) 0.30 0.08 0.88 0.02 0.0 0.40 0.16 0.94 0.06 0.04 0.50 0.27 0.97 0.14 0.11 0.60 0.40 0.98 0.26 0.21 0.70 0.53 0.98 0.39 0.35 0.80 0.68 0.99 0.57 0.54 0.90 0.84 0.99 0.77 0.76 1.00 1.00 1.00 1.00 1.00 It will be noted that the agreement between the calculated points and the observed data is rather good. Further investigation of the above method for obtaining relative permeabilities may be merited. For many sands within specified ranges of saturations the following relationship has been found to hold approximately': — =SW"......(7) Rs The exponent n in the above equation has been found to equal two for many sands so that equation (6) reduces to the following: The writer acknowledges the permission of The Texas Co. to submit this note for publication. 1. Walter Rose and W. A. Bruce—Jnl. of Pet. Tech., Vol. 1, No. 5, p. 127 (1949). 2. Walter Rose—Jnl. of Petr. Tech., Vol. 1, No. 5, p. 111 (1949). 3. G. E. Archie— -Trans. AIME, 146, 54 (1942). 4. M. C. Leverett— Trans. AIME, 142, 152 (1941). 5. M. C. Leverett—Trans. AIME, 132, 149 (1939).

Jan 1, 1949

By Owen Thornton

Recently equations have been presented by Rose and Bruce' and by Rose², showing how the relative permeability of a reservoir rock may be determined from the capillary character of the rock. In particular, equations were developed to show the relationship between capillary pressure and the effective permeability to the wetting phase in a poly-phase flow system. The equations are as follows (nomenclature the same as in the Rose and Bruce paper) Rose and Bruce assume that the average length of path (L,), which the wetting fluid follows in flowing through a porous media is independent of the saturation to the wetting phase, so that 1 is a constant dependent only on the k rock, and the permeability to the wetting phase is a function of the saturation and of the capillnry pressure: In measuring the flow of ekctric current through partially saturated core samples, it has been observed that the electrical resistance usually is not a simple linear function of saturation. This fact indicates that the average length of path in the flow of electric current is not independent of saturation, but rather that the tortuosity of the path depends upon the average saturation to the conducting fluid as well as upon the characteristics of the rock. itself. Inasmuch as the flow of fluid and the flow of electric current in many respects are analogous, it may be indicated further that the length of path for fluid also may not be independent of saturation. The following relationship can be derived to express the resistance to flow of electric current through a core sample partially saturated with conductive wetting phase, the non-wetting phase being non-conductive: where L is the average length of path followed by the current in flowing through a length L of partially saturated core, where L is the length of current path when the core is fully saturated, and where Rs and R, are the specific resistivities of the partially saturated and saturated core sample, respectively. It will be noted that R., the specific resistivity of the core sample when S, = 1.0, is equal to the "formation resistivity factor"' multiplied by the specific resistivity of the saturating fluid. If it be assumed that the average lengths of path for fluid flow and for the flow of electric current are the same, then equation (5) may be combined with equations (l), (2) and (3) to give the following relationship: The above equation suggests including a correction for tortuosity when calculating the relative permeability of a reservoir rock to a wetting phase. The correction factor may be obtained from the resistivity-saturation relationship. For instance, the following calcu- lations are obtained for the unconsoli-dated sands described by Leverett Kw Kw Sw R°/Rs Pt/Pc¹ (Calc.) (Obs.) 0.30 0.08 0.88 0.02 0.0 0.40 0.16 0.94 0.06 0.04 0.50 0.27 0.97 0.14 0.11 0.60 0.40 0.98 0.26 0.21 0.70 0.53 0.98 0.39 0.35 0.80 0.68 0.99 0.57 0.54 0.90 0.84 0.99 0.77 0.76 1.00 1.00 1.00 1.00 1.00 It will be noted that the agreement between the calculated points and the observed data is rather good. Further investigation of the above method for obtaining relative permeabilities may be merited. For many sands within specified ranges of saturations the following relationship has been found to hold approximately': — =SW"......(7) Rs The exponent n in the above equation has been found to equal two for many sands so that equation (6) reduces to the following: The writer acknowledges the permission of The Texas Co. to submit this note for publication. 1. Walter Rose and W. A. Bruce—Jnl. of Pet. Tech., Vol. 1, No. 5, p. 127 (1949). 2. Walter Rose—Jnl. of Petr. Tech., Vol. 1, No. 5, p. 111 (1949). 3. G. E. Archie— -Trans. AIME, 146, 54 (1942). 4. M. C. Leverett— Trans. AIME, 142, 152 (1941). 5. M. C. Leverett—Trans. AIME, 132, 149 (1939).

Jan 1, 1949

By M. H. Gaskell, D. M. Kehn, G. T. Pyndus

A correlation of the bubble point pressure for black oil systems is developed using the standard physical-chemical equations of soiutions. The correlation is based on 158 experimentally measured bubble point pressures of 137 independent systems and is expressed in terins of the usually measured field pnrameters— flash separation gm-oil ratio, rank oil gravity, total gas gravity, and reservoir temperature. The data were obtained on systems produced in Canada, Western and Mid-Continent01 United States, and South America. The average error (algebraic) in the representation is 3.8 per cent, and the maximum error encountered is 14.7 per cent. INTRODUCTION In the absence of experimentally measured properties of reservoir fluids, it is often necessary for the field engineer to make estimates regarding the fluid properties based on the usually measured producing parameters. To aid in these estimations, various correlations have appeared in the literature in recent years. Among the pertinent properties of interest is the bubble point pressure. A correlation for this parameter has been reported by Standing'. However, this correlation was based essentially on California produced crudes and this limitation was pointed out with its presentation. The correlation presented in this paper utilized data on crude oil systems from Canada, Wes- tern and Mid-Continental United States, and South America. CORRELATION DEVELOPMENT The basic assumption used in this development is the same as employed by Standing', There is a wide variety of ways to combine these parameters; however, in this instance the combination was made on the basis of Henry's law2. Accordingly, the relationship proposed is Although Eq. 2 defines an individual system, it is of limited value since H' is a function of gas-phase composition and the system temperature. It was observed that for the systems where the bubble point was measured at several temperatures that the ratio of the bubble point pressures and the ratio of the corresponding absolute temperatures (R) were practically identical. Thus, for correlation purposes the bubble point pressure may be taken as a direct function of the absolute temperature. This relation is valid only for those systems that are not near the critical point. Accordingly, this correlation will be inadequate for systems in the region of the critical point. The solubility of the various hydrocarbons found in the gas phase increases with the molecular weight. Thus, the saturation pressure should be inversely related to the gas gravity. Applying these principles to Eq. 2 and rearranging terms gives: The variables 02 the left side of Eq. 3 were designated as the "hubble point pressure factor". The number of mols of tank oil per barrel is a function of the "mclecular weight" of the tank oil. Although the tank oil is a complex mixture, it was assumed for the purposes of this correlation that a unique molecular weight could be assigned to a given oil. This was designated as the "effective molecular weight", and was related to the oil gravity, This empirical relationship was developed simultaneously with the correlation by assuming values of M,. and working to obtain a smooth curve for both the correlation and the effective molecular weight. The relationship between the oil gravity and the effective molecular weight used in this correlation is shown in Fig. 1. The effective molecular weight is somewhat higher than the molecular weight of the C fraction. The difference between these values is largest for the low-gravity systems. It is noted that this effective molecular

By N. J. Grant, D. S. Bloom

THE development of high temperature, high stress alloys had proceeded with such rapidity during the war, and for a short time afterward, that our knowledge of the constitution of the alloys had become seriously inadequate. To interpret correctly alloy behavior it is not only necessary to recognize the phases present, but also to know the properties of the phases under all varieties of conditions and treatments. Chromium in these high temperature alloys holds the unique distinction of being the only one element which must be present when an oxidizing or generally corrosive atmosphere is present and when a long life is desired in service. Carbon and nitrogen must also be considered where chromium is present. Carbon is always present, either as an impurity in the raw alloying elements, or as a deliberate addition agent to increase the strength. Nitrogen is generally picked up from the atmosphere during melting or may be added as an alloying element. The effect of nitrogen additions is not too dissimilar to that of carbon additions. As such, chromium carbides and nitrides become of great interest since they are present in a very large number of alloys, including alloy steels, stainless steels, super alloys, and the like. In the chromium-carbon system there are three accepted, carbides: Cr,C, Cr7C8, and Cr3C2. The existence of one more carbide, a still higher carbon form CrC, has been advanced. The phase diagrams of chromium and carbon as published by Friemann and Sauerwald² and by Tofaute, Kuttner and But- tinghaus³ -do not extend beyond the carbide Cr3C2, which contains 13.3 pct carbon; but Hatsuta has extended the diagram up to 20 pct carbon, and in doing so hypothesized, with the use of some questionable experimental results, the compound CrC. This carbide would contain 18.75 pct carbon, 81.25 pct chromium, by weight. It is further known that as the chromium carbides increase in carbon the acid resistance increases but the oxidation resistance decreases4,5 This is of great importance in high temperature alloys where time-temperature stability, as well as oxidation resistance, is of prime importance. The possible existence of a carbide of the formula CrC thus becomes of prime importance and it was considered important to recheck the chromium-carbon binary constitutional diagram for such a compound. In view of the wide spread of values listed for the melting point of chromium (1500° to 1850°C) and 1930°C8, it was considered .that the liquidus temperatures might well be redetermined more ac-

Jan 1, 1951

By J. J. Pye, J. B. Drew

The surface-diffusion coefficients of Ni63 diffusing on low-index planes of nickel single crystals have been measured over the temperature range from 400° to 1000°C using a precision autoradio-gvaphic technique. The activation energy for sur -face diffusion appears to he the same on the {111}, {110), and (100) planes and amounts to -0.60 ev. This is in good agreement with the value (-0.62 ev) reported for (111) planes obtained by mass-transport techniques. In an earlier paper, the authors have reported self surface-diffusion coefficients on silver.' In that work, a deviation of the diffusion coefficients from linearity in the Arrhenius plot was observed at high temperatures. This effect was attributed to a loss of tracer atoms into the bulk by volume diffusion. The purpose of the present work was to extend the technique developed to the nickel surface-diffusion system up to the point where volume diffusion would come into play. The nickel system especially lends itself to this technique due to the high efficiency of the isotope in darkening the film and the large absorption of the weak radiation (0.063 mev /3- particle of the trapped tracer atoms. The diffusion coefficients and ictivation energy for different orientations on nickel can also be compared with a report published by Blakely and Mykura 2 where a mass-transfer technique was used. This paper reports the self surface diffusion of nickel on the low-index planes over a wide temperature range using a precision autoradiographic technique. EXPERIMENTAL PROCEDURE The experiment is similar to that described in the earlier publication consisting of a radioactive needle as a source resting on a flat, smooth, chemically polished surface annealed in a dynamic dry-hydrogen atmosphere. The needle is held snugly on the surface by a holder fabricated from commercially pure nickel. The point source is made by grinding down a small-diameter nickel rod until a tip of approximately 0.1 mm radius is formed. It is then etched and the needle tip plated with the radioactive isotope Ni63. Nickel single crystals were used whose main impurities were spectrographically determined as Co 0.05, Fe 0.007, C 0.005, and S 0.003 pct. The surfaces, oriented to within 1/2 deg of the low-index planes, were carefully mechanically polished and etched in a 50-30-10-10 hot solution of acetic, nitric, sulfuric, and phosphoric acids giving a smooth polished surface. The crystals were then washed in distilled water and alcohol. Annealing temperatures ranged from 400° to 1000°C with a furnace arrangement in which the crystals could be brought up to temperature in times short compared to diffusing times. The temperature was maintained constant to ±10°C. In the temperature range investigated, the ratio of the surface-diffusion coefficient to the volume-diffusion coefficient (Ds/Du) was 105 or more and the mean bulk-penetration values, calculated from literature values of volume-diffusion coefficients,3 were on the order of 10-5 cm. After the diffusion anneal, the sintered needle is removed, and both the radius of the needle point and spot left on the crystal face are measured. The crystal is then placed on photographic film. Diffusion profiles are obtained by scanning the film with a recording microdensitometer which has a slit width of 10µ. DISCUSSION AND RESULTS The experimental conditions are such that the source strength and needle radius are essentially constant and the time is adjusted such that the mean bulk penetration is small. An exactly analogous heat-flow problem has been considered by Carslaw and Jaeger4 and the solution can be written in integral form as:

Jan 1, 1964

By Edward Gridley

Members of the Institute who were present at the Amenia, N. Y., meeting, in October, 1877, will remember their visit to the hematite mines, just west of the village of Amenia, and some of them may perhaps recall the deposit of carbonate ore south of the opening made for the hematite. The smelting of this carbonate during the last few months, has produced an iron that seems worthy of being brought to your notice. A little more than a year ago, at the Wassaie Furnace, Dutchess County, N. Y., we made a few hundred tons of iron from a mixture of two-thirds ram carbonate and one-third Chateaugay ore, hoping that it would be suitable for steel purposes, but as the iron showed phosphorus 0.189 per cent., it, was not offered. This iron looked well and seemed quite strong, and gave good results in malleable castings; but no special tests of strength were made. About February 1st, of this year, we began using two-thirds roasted carbonate, and one-third Chateaugay, and noticing that the iron mas stronger than usual, we had two samples tested, which showed tensile strength of 32,014 and 34,176 pounds per square inch. After our stock of Chateaugay ore was exhausted, me put on one-third ram carbonate with the two-thirds of roasted carbonate, and the first test made of the iron, showed 40,008 pounds per square inch. The three tests given above were made by Mr. A. J. Copp and Mr. E. B. Manning, of the Phoenix Furnace, Millerton, N. Y., on a machine of Riehle Bros., Philadelphia. Since these tests were made, they have broken samples made with all carbonate ore as follows: 39,669, 40,816, 41,882, 42,281, 39,902, and 40,130 pounds per square inch. A test taken from the same bed of iron as the last-mentioned (40,130), was broken by Mr. A. Blass, at Irondale Furnace, showing 40,151 pounds per square inch. A sample broken on the Riehle Bros. machine, at Stevens Institute, under direction of Professor R. H. Thurston, showed 40,000 pounds per square inch. Another sample was broken by Professor Thurston on his torsion machine, and gave torsion 7", and tensile strength of 44,500 pounds. And

Jan 1, 1884

By Woolsey McA. Johnson

In metallurgical circles it is known widely, but somewhat vaguely, that the ease of reduction of metallic oxides depends largely on the way they hare been prepared. It is likewise known that different forms of carbon have different and greatly varying reducing powers. It is the purpose of this paper to show somewhat more definitely and scientifically these facts. Some years ago the writer published an account of pyrometric determinations of the reduction temperature of zinc oxides variously prepared and of several kinds.' In said paper it was shown that the temperature at which zinc oxide evolves zinc according to the equa-tion ZnO + C = Zn + CO depends upon the nature of the two reacting bodies. The determina-tions had a range of accuracy of from 2° to 6°C., whereas differences were found to amount to an extreme of 90' C. So the differences are real ones and must have a definite cause. The equation of boiling water, (H2O)4 D 4 (H2O) has a fixed temperature for equilibrium of 100° C. at 760 mm. pressure. In general, all equations reacting in the liquid or the gaseous phase have well-defined constant physical conditions which govern the equilibrium point and reaction velocities. In a reaction where we have one or more solid phases, the tempera ture conditions requisite for the unbalancing of the stable system are found to vary. These variations are due to the fact that in a solid there is a very complex molecule and it is not a question solely of the tearing away of two interlocked atoms, but also of the destruction of a complex molecule containing hundreds, or possibly thousands, of smaller molecules. In other words, there are two forces to be overcome: a certain

Jan 1, 1914

By W. T. Jr. Thom

IN PREVIOUS classifications of coal, it has been customary to regard moisture eliminated from coal samples between 20° and 100° C. as extraneous matter, rather than as a constituent part of the coal. It seems, however, that the physical character and use properties of the low-rank coals are directly related to the amount of such moisture present, and recent chemical work has shown1 that such coals contain unstable groupings which decompose between 20° C. and temperatures somewhat above 100° C., with the splitting off of moisture. According to this view, the moisture eliminated from air-dried coal below boiling point is similar in all essential respects to moisture eliminated above 100° C., and is produced by analogous reactions; and inasmuch as the moisture given off above 100° C. has always been treated as a constituent of the volatile matter of coal, it would seem that consistent usage would include as a part of the volatile matter all moisture present as an essential component of the coal as it occurs in nature. As a matter of experience, it seems clear that the general physical and chemical characteristics of the low-rank coals are largely determined by or related to the moisture, whether chemically or physically combined, present in air-dried coal; it is also demonstrable by trial that the low-rank coals cannot be satisfactorily classified on a purely chemical basis by using the moisture free form of analysis. The low-rank coals of the western United States include numerous well-defined types, many of which were referred to in a classification proposed by Ashley,2 in which the physical and use properties of the coals were made the primary basis for their systematic grouping. When testing this classification by replotting analyses of these type coals according to the Seyler scheme of classification,3 a satisfactory parallelism between use properties and chemical constitution of the dry coal was found among

Jan 5, 1925

By W. T. Thom

In previous classifications of coal, it has been customary to regard moisture eliminated from coal samples between 20 and 100 C. as extraneous matter, rather than as a constituent part of the coal. It seems, however, that the physical character and use properties of the low-rank coals are directly related to the amount of such moisture present, and recent chemical work has shown' that such coals contain unstable groupings which decompose between 20 C. and temperatures somewhat above 100" C., with the splitting off of moisture. According to this view, the moisture eliminated from air-dried coal below boiling point is similar in all essential respects to moisture eliminated above 100" C., and is produced by analogous reactions; and inasmuch as the moisture given off above 100" C. has always been treated as a constituent of the volatile matter of coal, it would seem that consistent usage would include as a part of the volatile matter all moisture present as an essential component of the coal as it occurs in nature. As a matter of experience, it seems clear that the general physical and chemical characteristics of the low-rank coals are largely determined by or related to the moisture, whether chemically or physically combined, present in air-dried coal; it is also demonstrable by trial that the low-rank coals cannot be satisfactorily classified on a purely chemical basis by using the moisture free form of analysis. The low-rank coals of the western United States include numerous well-defined types, many of which were referred to in a classification proposed by Ashley,2 in which the physical and use properties of the coals were made the primary basis for their systematic grouping. When testing this classification by replotting analyses of these type coals according to the Seyler scheme of classification,3 a satisfactory parallelism between use properties and chemical constitution of the dry coal was found among

Jan 1, 1925

Jan 1, 1967

Jan 1, 1970

By Carl Henrich

Jan 1, 1893

By William M. Bowron

THIRTY years ago, when I stood on the cliff of red fossil iron-ore, on Red mountain, Jefferson county, Ala., I asked what were the geological relations of this remarkable deposit. In reply I was told that it was a limestone colored and saturated by some unknown but wholly external influences, and that at a reasonable distance from the surface the color would disappear. I could find no satisfactory explanation either of the nature of this wonderful external permeating influence, or of the cause of such a ferrous impregnation selecting this one particular bed of limestone, to the exclusion of the higher and lower beds of the same material which are not even stained. I. THE PRESENT THEORY. Referring to this subject, Dana says:' "The clays, clayey sandstones and limestones of the Clinton epoch, through New York and the Appalachians, show that the mud-flats and sand-banks, and hence the shallow seas of the coast region, still continued. . . The beds of argillaceous iron-ore, which spread so widely through New York and some of the other States, south and west, could not have formed in an open sea, for clayey iron-deposits do not form under such circumstances. They are proof of extensive marshes, and, therefore, of land near the sea-level. The fragments of crinoids and shells found in these beds are evidence that they were, in part at least, salt-water marshes, and that the tides sometimes reached them." At first, this explanation seemed satisfactory, but the more I studied the ore the less satisfying the explanation became. 1. In the ore itself I found associated with the small particles of rounded matter (now consisting of iron oxide in which organic structure, if ever present, has become lost, though the

Nov 1, 1905

By MCA Woolsey

(Butte. Meeting, August, 1913.). IN metallurgical circles it is known widely, but somewhat vaguely, that the ease of: reduction of metallic oxides depends largely on the way they have been prepared. It is likewise known that different forms of carbon have different and greatly varying reducing powers. It is the purpose of this paper to show somewhat more definitely and scientifically these facts. Some years ago the writer published an account of pyrometric determinations of the reduction- temperature of zinc oxides variously prepared and of several kinds.1 In said paper it was shown that the temperature it which zinc oxide evolves zinc according to the equation Zn0. +' C = Zn + CO depends upon the ;nature of:., the.' two reacting bodies. The determinations bad a range of accuracy of from 2° to. 6° C.,whereas differences were found to. amount to an extreme. of 90° C. :.86 the differences are real ones and must have, definite cause. The equation of boiling water, (H20)4 = 4 (H2O) has a fixed temperature for equilibrium of 100° C. at 760 mm. pressure. , In general, all equations. reacting e in .the liquid or the gaseous phase have-well-defined constant physical conditions which govern the equilibrium point and reaction velocities. In a reaction where we have one or more solid phases, the temperature conditions requisite for the unbalancing of the stable system are found to vary. These variations are due to the fact that in a solid there is a very complex molecule and it is not, a question solely of the tearing away of two interlocked atoms, but also of the destruction of a complex molecule containing hundreds, or possibly thousands, of smaller molecules.

Jan 7, 1913

By W. H. Hough, P. B. Leavenworth

Development during 1942 led to the discovery of 26 new fields in the Texas Gulf Coast, as compared with 27 during 1941. Of these, 19 are classed as oil fields, 4 distillate fields, and 3 gas fields. Production from the new fields amounted to 614,467 bbl. to October 1942. Producing Sections.—Discoveries in I942, compared with the previous two years, classified by producing formations, are shown in the following table: It is interesting to note the increase in Wilcox discoveries due to the extensive geophysical campaign that has been con. ducted since 1940. Drilling.—During the year 688 wells were drilled, of which 574 produced oil or gas and 114 were dry. This represents a considerable decline in activity over the previous year, when 1405 wells were drilled in the area, of which 1081 were producers and 324 failures. Jackson County continued to hold the lead, with 222 wells completed. Production.—-Despite curtailed drilling, production amounted to 118,009,451 bbl. for 1942, indicating a slight increase over the 113,726,893 bbl. produced during 1941. The statistics in Tables I and 2 include condensate and distillate as oil production, because many Gulf Coast fields produce oils with a wide variation of specific gravities, all of which are commingled in pipe lines. Table 3 shows by counties most of the activities referred to. The number of wells drilled includes only field wells; not wildcats. Outstanding Fields of 1942 The Texas Gulf Coast covered in this report has 270 more or less active oil and gas fields, including the new discoveries of 1942. Of these the most outstanding from the standpoint of production are listed in Table 4. Each of these fields produced one million barrels or more during 1942. Some of the fields where new extensions are occasionally referred to as separate fields, such as West Columbia and New West Columbia, or Thompson and South Thompson, are combined to give a more accurate outline. Two interesting facts may be noted from this list of some 26 oil fields: (I) that the Lolita field, Jackson County, is the only discovery since 1938 to produce more than one million barrels annually, although there have been 79 discoveries since Jan. I, 1940; (2) that 20 of these 26 fields produce from the Frio. New Fields ALief, Harris County.—Pure Oil Company's No. I Mike Albanese was drilled to 8637 ft. in Cook Mountain shale. After numerous tests the well was completed on Apr. 20, 1942, in a Yegua sand at 7919 to 7924 ft. for 54 bbl. of 52' gravity oil and 3,335,000 cu. ft. of gas through

Jan 1, 1943

By W. H. Hough, P. B. Leavenworth

Development during 1942 led to the discovery of 26 new fields in the Texas Gulf Coast, as compared with 27 during 1941. Of these, 19 are classed as oil fields, 4 distillate fields, and 3 gas fields. Production from the new fields amounted to 614,467 bbl. to October 1942. Producing Sections.—Discoveries in I942, compared with the previous two years, classified by producing formations, are shown in the following table: It is interesting to note the increase in Wilcox discoveries due to the extensive geophysical campaign that has been con. ducted since 1940. Drilling.—During the year 688 wells were drilled, of which 574 produced oil or gas and 114 were dry. This represents a considerable decline in activity over the previous year, when 1405 wells were drilled in the area, of which 1081 were producers and 324 failures. Jackson County continued to hold the lead, with 222 wells completed. Production.—-Despite curtailed drilling, production amounted to 118,009,451 bbl. for 1942, indicating a slight increase over the 113,726,893 bbl. produced during 1941. The statistics in Tables I and 2 include condensate and distillate as oil production, because many Gulf Coast fields produce oils with a wide variation of specific gravities, all of which are commingled in pipe lines. Table 3 shows by counties most of the activities referred to. The number of wells drilled includes only field wells; not wildcats. Outstanding Fields of 1942 The Texas Gulf Coast covered in this report has 270 more or less active oil and gas fields, including the new discoveries of 1942. Of these the most outstanding from the standpoint of production are listed in Table 4. Each of these fields produced one million barrels or more during 1942. Some of the fields where new extensions are occasionally referred to as separate fields, such as West Columbia and New West Columbia, or Thompson and South Thompson, are combined to give a more accurate outline. Two interesting facts may be noted from this list of some 26 oil fields: (I) that the Lolita field, Jackson County, is the only discovery since 1938 to produce more than one million barrels annually, although there have been 79 discoveries since Jan. I, 1940; (2) that 20 of these 26 fields produce from the Frio. New Fields ALief, Harris County.—Pure Oil Company's No. I Mike Albanese was drilled to 8637 ft. in Cook Mountain shale. After numerous tests the well was completed on Apr. 20, 1942, in a Yegua sand at 7919 to 7924 ft. for 54 bbl. of 52' gravity oil and 3,335,000 cu. ft. of gas through

Jan 1, 1943