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By John S. Bell, J. M. Shepherd

pressure difference of 280 psi measured initially on opposite sides of the major fault in the Hawkins Field led to pressure determinations in the Woodbine sand throughout the East Texas basin. Considering the large area, there is unusually good correlation between pressure losses and points of major withdrawals, these losses indicating that the basin pressure has been materially reduced by withdrawals, primarily from the East Texas Field and secondarily from the old fault-line fields of Limestone and Navarro counties, with the pressure loss varying inversely with the log of the distance from these two main areas of basin withdrawals to the measurement points. Apparently faults located throughout the basin serve as local blocks to continuous pressure gradients. INTRODUCTION The pressure anomalies found in the Hawkins Field, Wood County, Texas,' shortly after discovery have led to an area-wide investigation of the pressure distribution within the Woodbine sand of the East Texas basin. These pressures were obtained by drill-stem tests made for that sole purpose while drilling wildcat wells to deeper horizons. The Woodbine sand of Gulf Cretaceous Age is or has been productive of oil and gas in 42 different fields, with the 28 oil fields currently active having produced 118,000,000 bbl of oil during 1949. With one exception, producing energy for all Woodbine reservoirs has been from water drive provided predominantly by expansion of the tremendous volume of water contained in the Woodbine sand. This producing mechanism was recognized at an early date and was described mathematically by

Jan 1, 1951

By J. S. Ll. Leach, L. R. Rubin, M. B. Bever

The energies of formation of ordered and disordered solid solutions of composition CusAu and the energy of ordering in this alloy were determined by tin solution calorimetry. The degree of order was measured by X-ray diffraction and electrical resistance and microhardness measurements were made on ordered and disordered specimens. AMONG the phenomena associated with the order-disorder transformation of a solid solution, the change in internal energy is of special interest because of the part it plays in the various theories of ordering. Published values for the decrease in internal energy accompanying the formation of a superlattice from a disordered solid solution of composition CuAu range from —370 to —2260 cal per gram-atom. Some of these values represent calculations based on theory and others are the results of experimental measurements. The distinction between the change in internal energy, AE, and the change in enthalpy, AH, can here be neglected, because they are approximately equal for solid-state reactions at normal pressure. An analysis of ordering by Bragg and Williams' predicts an energy change of —605 cal per gram-atom for the formation of a superlattice in the alloy Cuau from a completely random solution. Peierls" application to Cuau of Bethe'sb earest-neighbor theory yields —560 cal per gram-atom for the formation of a superlattice from a matrix which initially contains short-range order. Cowley' extended the nearest-neighbor approach to include as many as five shells of neighbors; on this basis a change in energy of —500 cal per gram-atom is expected. Eguchi," using a quantum-mechanical treatment, calculated a value of —2260 cal per gram-atom for the difference in the energy of completely disordered and completely ordered Cu,Au. Sykes and Jones- eated a completely ordered alloy and measured its heat capacity as a function of temperature. This measured heat capacity agrees closely with the corresponding value found by the Kopp-Neumann (or mixture) rule up to about 250°C and above this temperature exceeds it, especially near the critical temperature for ordering. The difference between the integrals with respect to temperature of the observed and the Kopp-Neumann heat capacities was considered to be the energy of ordering. By this method Sykes and Jones found a value of —530 cal per gram-atom. This value is not adjusted for the short-range order remaining above the critical temperature. The pres- ence of such short-range order is suggested by the difference between the measured heat capacity and the extrapolated Kopp-Neumann heat capacity immediately above the critical temperature. Values reported by Weibke and von Quadt' and by Hirabayashi, Nagasaki, and Maniwaa were obtained in the course of investigations primarily aimed at other objectives. Weibke and von Quadt measured the temperature coefficient of the electromotive force of a Cu-CuAu cell. They obtained a value of —1010 cal per gram-atom for the heat of formation of the alloy at 500°C, at which temperature there is no long-range order. They also obtained —1380 cal per gram-atom as the heat of formation of the ordered alloy at 370°C. Considering the heat of formation of the disordered alloy to be independent of temperature, they estimated the energy of ordering at 370°C as —370 cal per gram-atom. At this temperature long-range order is incomplete and the degree of order changes rapidly with temperature. Hirabayashi, Nagasaki, and Maniwa," using an annealing calorimeter, investigated an alloy containing 23.4 rather than 25.0 atomic pct Au and thus could not obtain complete order. Thelr value of the energy of ordering was —490 cal per gram-atom. Orianis has recently investigated the Au-Cu system by the galvanic emf technique. He reports values for the heats of formation of Cu-Au alloys, from which the heat of formation at 427 OC of an alloy of composition CuAu may be found by interpolation. This value is —1080 cal per gram-atom. In the work here reported, disordered and ordered alloys of composition CuAu and corresponding mixtures of gold and copper were dissolved in liquid tin and the heat effects measured. These heat effects are small, since the dissolution of gold in tin is exothermic and the dissolution of copper is endothermic. The method, therefore, yields fairly precise values of the heats of formation of disordered and ordered alloys and of the energy of ordering. Experimental Procedure The calorimeter consisted of a long-necked Dewar flask immersed in a constant temperature salt bath and has been described by Ticknor and Bever." The chief changes in this equipment were an improvement in vacuum and the replacement of the mercury thermoregulator by a resistance thermometer control circuit. The solvent, which was maintained at a constant temperature near 350°C, consisted of 500 grams of 99.99 pct pure tin. The solute samples were mixtures of gold and copper in the proportion corresponding to the composition Cu,Au or solid solutions

Jan 1, 1956

By D. A. Flanagan, B. L. Landrum, P. B. Crawford, B. C. Norwood

Herern is described a heat conduction model which has been developed to predict the pressure distribution within a reservoir being subjected to rrnsteady-state depletion. Although potentiometric models have been widely used to study reservoir pressure distribution, their application is limited to the study of steady-state cases. Electrical analyzers may be used to study unsteady-state phenomena, but their application and simulation have certain limitations. Much of the now accepted theory of unsteady-state fluid flow in porous media has evolved from previous heat conduction knowledge. An analogy between the flow of fluid in an unsymmetrical reservoir and con-duct ion of heat in a similarly shaped unsymmetrical metal plate is made to show adaptability of the hear conduction principle to transient reservoir cases. A description of the model and necessary instrumenrarion is included. Data show influence of well location on pressure distribution during unsteady-state deple[ion. Application of results is made to a hypothetical reservoir and to a reservoir located in an irregular aquifer. INTRODUCTION Development of methods for predicting behavior of petroleum reservoirs has resulted partially from adaptation of electrical and thermal flow concepts to the flow of fluids through porous media. Extensive investigation of electrical and thermal flow problems has resulted in mathematical solutions applicable to many reservoir problems. The relative ease of measuring electrical flow has brought wide acceptance of the use of the potentiometric model to study certain field problems. Potentiometric models are restricted to the study of steady-state conditions because of the instantaneous response of electrical flow to changes in the applied potential. The electrical reservoir analyzer has been one of our most useful instruments for studying certain phases of unsteady-state behavior1. Other than approximation techniques, no method exists for determining pressure distribution in an irregular reservoir during primary depletion. Heat flow, like fluid flow, is inherently transient. The model described here was developed to use this transient nature of heat flow, measurable in the laboratory, to simulate transient flow of fluids in the porous medium of the reservoir above the bubble point. A metal plate shaped like the reservoir to be studied was heated by a "well" source. Temperature increase in the plate is analogous to pressure decline in the field if the field is being depleted, or pressure increase if fluid is being injected. This study is intended to determine the feasibility of using the transient nature of the heat flow to study the transient behavior of fluid flow. It is hoped that this new technique will aid in the understanding of one of the more complex phases of reservoir engineering. THE FLUID FLOW-HEAT CONDUCTION ANALOGY The similarity of the equations which describe the flow of fluids through a porous medium and the conduction of heat through a solid is well known2. Rate of flow of fluids is given by Darcy's law3. while the rate of flow of heat is given by Fourier', (I,, - KA 4T........(2) Combining Eq. 1 with the equation of continuity for a compressible liquid", i.e.,results in Expressing y in terms of the compressibility, i.e., pr = peey ,..........(5) and by expanding the exponential and neglecting higher orders of cp one can obtain

By G. R. Mansfield, W. B. Lang

THE third year of Government exploration for potash by the U. S. Geological Survey and the U. S. Bureau of Mines under the authorization of the act approved June 25, 1926 (Public 424-69th Cong.) is drawing to a close. The results thus far obtained are thought to be sufficiently interesting and satisfactory to justify the presentation of a brief preliminary account of the work. Review of Earlier Exploration The general geologic similarity of the Permian basin of Texas and New Mexico to the potash field of Germany had long ago suggested the possibility of the presence of potash salts somewhere in that basin, but petroleum exploration was then making little headway there and the necessary data could not be obtained. The discovery by Udden in 1912 of potash in brine from the Spur well in Dickens County, Texas, was the first direct evidence of its presence. In 1915-17 the U. S. Geological Survey drilled a test well with standard tools at Cliffside near Amarillo, but failed to find potash. Nevertheless, an observer has been kept in the field, at first in cooperation with the Texas Bureau of Economic Geology but since 1922 by the Survey alone, to secure data and samples from oil and gas tests. Since the discovery of oil in Reagan County in 1923 exploration by drilling has been rapidly extended to many parts of western Texas and southeastern New Mexico. The identification of the potash-bearing mineral polyhalite was first announced by the Geological Survey in June, 1921, the material having come from cuttings from the Bryant well in Midland County and the Burns well in Dawson County, Texas. Successive discoveries and announcements of similar purport aroused widespread interest in potash exploration, which culminated in the action by Congress already noted. Permian Salt Basin The Permian salt basin extends generally northeastward from western Texas and southeastern New Mexico through the Panhandle sections of

Jan 1, 1929

By McIntosh F. Galbraith

This paper describes the use of the magnetometer, under geological direction, in exploration of the Sudbury nickel district. The writer's experience at Falconbridge has led him to the belief that only through detailed work, and by careful correlation of both geological and geophysical results, can geophysical prospecting methods be applied successfully to mining exploration problems. It is hoped that the basic technique described in the paper will be found to have general application.

Jan 1, 1942

By O. A. Knight, Helmut Muller-Stock

The suppression of the austenite-martensite transformation that can be brought about by the addition of certain alloying elements, such as manganese or nickel, to plain carbon steel has been known for a long time, especially since Guillet's investigation at the beginning of this century. The extent to which the critical range is lowered depends upon the percentage and nature of the special element added. First the Arl point is lowered gradually, then at a certain percentage a sudden lowering to about 300" C. occurs. The addition of still larger percentages of the alloy may result in lowering the Ar, point to room temperature or below, in which case the steel remains austenitic at room temperature, especially after rapid cooling. The effect of alloying elements of this general type on the lowering of the transformation temperature is well illustrated by Sauveur(lJ$ in his Fig. 281a, reproduced here as Fig. 1. This type of curve is characteristic of both manganese and nickel though it requires about 21/2 times as much nickel as of manganese to produce the same result. The influence of nickel in retarding the transformation of austenite into the lower transition constituents is due to its lowering of the critical range of the steel, which is also well illustrated by Sauveur'l) (after Osmond) in his Fig. 284, reproduced here as Fig. 2. Scott('" presents a diagram illustrating the effect of manganese on the Ac3 and Ara points which is strikingly similar to the diagram above referred to in Fig. 2 concerning the effect of nickel. Lowering the critical range has the effect of increasing the viscosity, or, rigidity, of the alloy at the time when it is undergoing its transformation, which greatly slows down the transformation reaction velocity, and this, in turn, makes it easier to suppress, wholly or in part, the transformational changes. Reaction rates are normally much slower at low

Jan 1, 1934

By William L. Fink, L. A. Willey

Since so many different curves have been published for the solid solubility of zinc in aluminum, it seems desirable to definitely establish the correct curve by two or more independent methods. The curve published in part I1t was based entirely upon X-ray measurements because the other methods employed at that time were not satisfactory. The present paper (the seventeenth of this series on high-purity aluminum alloys) describes the determination of the solid solubility of zinc in aluminum by the measurement of electrical resistivity at temperature and by microscopic examination. Since the publication of our part I in 1932, an investigation of the solubility relations in the aluminum-zinc system has been reported by Schmid and Wassermann2, who obtained their solubility results from lattice-parameter measurements on heat-treated and quenched specimens. The diagram that they published is shown in Fig. 1. In this investigation they also found by X-ray measurements that the parameter of the gamma phase changed continuously with zinc content and at such a rate that it would be identical with that of the beta phase at 60 atomic per cent zinc. It was concluded therefore that the beta and gamma phases, from the point of view of structural relationship, are one single phase. They also suggested a gap of immiscibility between 270" and 350" C. The complete boundary in this region could not be determined satisfactorily by the method employed and therefore was not shown in their diagram. Aluminum-zinc Alloys Materials Used.—Electrolytically refined aluminum3 was used in preparing the alloys for the work reported in this paper. Chemical analysis showed the following impurities: 0.004 to 0.005 per cent silicon, 0.006 to 0.008 per cent iron and 0.005 to 0.006 per cent copper. Also,

Jan 1, 1936

By Arvid E. Nissen, Knox Taylor, John H. Hall

Some months ago one of the authors was asked to write a paper on the heat treatment of steel castings that would be more comprehensive than other matter he had published; this is an attempt to present in condensed form the results of experimental work and actual practice carried out for the most part in 1907, 1908, and 1909. It is not a laboratory research and the work done was carried out for the express purpose of putting in practice the processes discovered as fast as possible. Most of the tests are the result of commercial practice and not of bars annealed in our laboratory; most of the micrographs were made for our own records and not for publication. Certain of the micrographs, therefore, are not as clear as we may wish but they were good enough for our purpose at the time they were made. The tests and micrographs are selected from several thousands in our files. All of these micrographs are magnified 60 diameters. These experiments were conducted almost entirely on steel made in a 3-ton bottom-blown converter, and most of the steel illustrated analyzes about 0.05 in phosphorus and sulfur. Unfortunately, a certain number of specimens are shown of which we do not have the complete analysis, but in most cases in which the phosphorus and sulfur vary much from the figure just given that fact is noted. For purposes of comparison, we have included a certain number of micrographs and tests of steel made in the electric furnace, some of which were from specimens made in other shops and some in our own shop, and some tests of acid open-hearth and tropenas steel. A brief examination of the tests in Table 1 shows that certain treatments of, for instance, 0.30 per cent, carbon steel are not represented by any test data. Had this been a laboratory research, this information would undoubtedly have been furnished, but as this work was done for commercial purposes the omissions are due to the fact that, at the time the work was done, we saw no advantage in trying every composition of steel with each treatment discussed in the paper.

Jan 1, 1920

By Knapp. Arthur

THE ORDINARY well log is subjected to a great deal of criticism, much of which is well founded. Sometimes, though, the difficulty in interpreting the log is due to the fact that the geologist or engineer using the logs does not know the limitations of the drilling method used. The rotary drill, especially, has inherent limitations that make it difficult, to secure .definite information at all times. The identification of well-defined key beds is about all that can be expected from the rotary log. The formation in a drilled hole, as reported by the driller; has a direct relation to the speed with which the drill makes the hole or to the reaction of the various strata on the bit, called the "feel of the bit." When this is not thoroughly understood by the geologist or engineer endeavoring to interpret the log, the result is an erroneous correlation with other wells or a discarding of the log as worthless. GENERAL TERMS Hard and Soft.-Hard and soft are relative terms. In the case of well logs, they are very misleading as they are used in connection with both resistance to abrasion and resistance to percussion. In technical rock classification, hardness is relative resistance to abrasion. The term brittleness is used in connection with resistance to blows. These terms are misleading to the geologist or engineer who is not familiar with both the cable-tool, or standard tool, method of drilling and the rotary method. In the case of the standard tools, the driller's report of the hardness of the formation is in terms of its resistance to blows. For instance, a cable-tool driller might be able to make from 30 to 50 ft. a tour in a brittle limestone, which he would call soft and at the same time he might call a relatively soft (from a purely mineralogical standpoint) gypsum hard, because it is somewhat elastic and is not readily broken by blows. The rotary driller would reverse the terms. The limestone is hard in that it resists the abrasive action of the bit, while the gypsum might be soft in that it is readily cut by the rotary bit. It is rare that wells drilled by the

Jan 2, 1920

By H. N. Egan

Faced with a severe disposal problem of their fines from a coal mine in the heart of the Appalachian Mountains of extreme eastern Kentucky, Eastern Coal Corporation has built a special plant to pelletize the fines into high quality coal pellets meeting the requirements of the metallurgical market. These low-ash, low-sulfur pellets measuring 3/4 x 3/8 in. contain less than 1.5% moisture and have the same stability as raw coal of the same size. Although Eastern Coal is mining 6000 tpd, the company had, until recently, no provision to recover the fine coal which was included with the plant effluent pumped to a 12-acre refuse pond. The pond, impounded behind the coarse refuse dump, rose 15 ft last year and obviously no pond can stand many years at this rate. Limited pond space in this rugged area of steep hills and narrow valleys dictated a revised disposal method.

Jan 11, 1967

By Bernard G. Carbajal

The dielectric properties and thermal stability of glow-discharge polytnerized films of styrene, chloro-benzene, and other organics and photoresist filrns are presented. Variations in the glow-discharge polymerization procedure are related to thermal stability. Thermal treatwzents to improve the dielectric properties of both positive (A2 340) and negative (KMER) photoresists are given. THIS study of the dielectric properties of thin organic polymer films is part of a program to investigate the electronic applications of organic materials. Thin organic polymer films have been produced in an ac glow discharge,13 with a low-energy electron-beam process,4 and in an rf dicharge. A process has been developed during the course of this program for forming thin organic polymer films in a dc glow discharge. These glow-discharge polymerized (GDP) films exhibit some useful dielectric and insulative properties. Variations in the properties of the GDP films can be induced by changes in the source material (monomer) andor in the conditions of the glow discharge. Thin organic polymer films can also be produced from typical positive and negative photoresists. Some variations in the properties of the photoresist films can be induced by suitable post-application treatments such as thermal crosslinking. The properties of interest in this study are dielectric constant, dielectric strength, resistivity, and thermal stability. POLYMER FILM PREPARATION I) GDP Films. The GDP films were prepared in a dc glow discharge in an atmosphere of organic monomer vapor. The details of the glow-discharge procedure have been presented previously.6 Briefly, under the influence of a dc glow discharge organic vapors can be polymerized in the vapor phase and the resultant polymer (GDP film) deposits on and in the vicinity of the cathode. Substrates placed behind a screen cathode can be uniformly coated over all exposed areas. Pattern definition can be achieved using normal mask stencil techniques. Table I presents the pertinent parameters in the preparation of GDP styrene. Conditions of Forrrzation of GDP Styrene. The rate of deposition for GDP films was monitored using a current-time integrator. The thickness of the deposited film for a given set of experimental conditions was a function of the current-time integral. The fifth row in Table I is a compilation of the deposition rate of GDP styrene films. Other organic monomers behave in a similar fashion. With the exception of the highly halogenated saturated hydrocarbons, all organics subjected to the conditions of the glow discharge form GDP films. 11) Photoresist Films. Photoresists are normally recognized to exist in two forms, a low molecular weight, soluble polymer form (A) and a high molecular weight, crosslinked insoluble form (B). Typical negative photoresists are applied in the low molecular weight form A and converted to the high molecular weight form B by the action of light. (Positive photoresists are applied in form B and converted to form A by the action of light.) Eastman Kodak Metal Etch Resist (KMER) has been chosen as a typical negative photoresist. Polymer film samples were prepared in the same configuration used for GDP films. The KMER was applied in the usual fashion using a 120°C drying step (infrared-lamp heating) and a 180°C post-bake. Care must be taken to completely remove the solvent in the drying step and to properly develop and postbake to exposed photoresist. If the photoresist film is not properly dried and postbaked, severe blistering and peeling will occur during subsequent elevated-temperature exposure. Thickness can be controlled by varying the viscosity of the form A photoresist and the spin rate at application. AZ 340 was chosen as a typical positive photore-

Jan 1, 1967

By K. A. Pauly

Compressed air has been and is still very extensively used in connection with mining-operations, but its application in the past has been almost entirely confined to supplying power to underground machinery. Its introduction was due to the difficulty of taking care of the steam which is exhausted underground, rather than to any advantage in efficiency to be gained by its use. The ease with which electric power may be carried to the remotest parts of the mine and the high efficiency of the electric motor have long been appreciated by mine-operators, and electric power is now extensively used underground in the more recent developments, while many of the compressed-air engines in the older workings are being rapidly replaced by electric motors. Recently, however, it has been suggested to use compressed air for driving the large shaft-hoists, the air for the engines being supplied by electrically-driven compressors, and an installation of this character is being erected at Butte, Mont. It is the object of this paper to compare the compressed-air system of hoisting with the various electrical systems, from the stand-points of first-cost and cost of operation. However, before entering into a discussion of the various systems, it will be well to consider briefly the conditions affecting the choice of a system of hoisting in which electricity is the ultimate source of power. The power required by a mine-hoist is extremely intermittent and fluctuates between very wide limits, the all-day average consumption of power not exceeding from 5 to 15 per cent. of the maximum demand during hoisting. The cost of supplying power for such a fluctuating load is necessarily higher than that for supplying an equal amount of

Jan 1, 1912

By F. McIntosh Galbraith

THIS paper describes the use of the magnetometer, under geological direction, in exploration of the Sudbury nickel district. The writer's experience at Falconbridge has led him to the belief that only through detailed work, and by careful correlation of both geological and geophysical results, can geophysical prospecting methods be applied successfully to mining exploration problems. It is hoped that the basic technique described in the paper will be found to have general application.

Jan 1, 1942

By Blake M. Loring

Recently the S-curves for 30 to 40 alloy steels have been pub1ished.l.2 These steels show individual characteristics, which make each additional S-curve of great interest. There are important differences in the mechanism of the transformation process, the type of transformation product, and the influence of alloying elements. Steels of the same general alloy composition may possess such variable characteristics with regard to the length of time of isothermal transformation that an S-curve for each heat of steel may be desirable. In the present work the isothermal transformation of a steel having the following composition and grain size was studied: 0.29 per cent carbon; 0.21 manganese; 0.026 phosphorus; 0.017 sulphur; 0.056 silicon; 1.45 chromium; 3.25 nickel; austenite grain size, 7. The progress of the isothermal transformation was followed by several different methods, including hardness measurements, dilatometer observations, and examinations of the microstructure. It was not expected that these methods would be in precise agreement.3 Accordingly, the changes in microstructure and hardness were given additional weight in determining the initial stage of transformation and the dilatometer measurements were relied on in estimating the completion of the process. The beginning of transformation was indicated by I per cent of transformation products and the end of transformation by about 99 per cent. The reproducibility of the various methods in the ranges of highest sensitivity was checked by several observations at each time and temperature. The steel used in this investigation was annealed for 24 hr, at 925°C. Macroetching revealed no serious segregation. The specimens for the metallographic and hardness investigations were 1¼ by ½ by ? in. Wires attached to the samples were used for handling. instead of tongs, to avoid chilling. The specimens were heated at 845°C. for ½ hr. and quenched into constant-temperature salt baths held at various temperatures from 205' to 650°C. The time required to transfer the specimens was found to be about 1½ sec., and nearly 5 sec. more was required for them to come to the temperature of the bath. After various lengths of time in the constant-temperature baths the specimens were quenched in water at 2I°C. The specimens were cut in half for the metallographic examination, to provide a surface free from decarburization. To determine the beginning and end of the transformation the percentage of transformation determined metallographically and by hardness was plotted against time. A planimeter was used in the metallographic determination. The hardness and metallographic determinations made at room temperature were confirmed reasonably well by dilatometer measurements taken during the process of transformation at the various temperatures. Two dilatometers were used to

Jan 1, 1942

By Blake M. Loring

Recently the S-curves for 30 to 40 alloy steels have been pub1ished.l.2 These steels show individual characteristics, which make each additional S-curve of great interest. There are important differences in the mechanism of the transformation process, the type of transformation product, and the influence of alloying elements. Steels of the same general alloy composition may possess such variable characteristics with regard to the length of time of isothermal transformation that an S-curve for each heat of steel may be desirable. In the present work the isothermal transformation of a steel having the following composition and grain size was studied: 0.29 per cent carbon; 0.21 manganese; 0.026 phosphorus; 0.017 sulphur; 0.056 silicon; 1.45 chromium; 3.25 nickel; austenite grain size, 7. The progress of the isothermal transformation was followed by several different methods, including hardness measurements, dilatometer observations, and examinations of the microstructure. It was not expected that these methods would be in precise agreement.3 Accordingly, the changes in microstructure and hardness were given additional weight in determining the initial stage of transformation and the dilatometer measurements were relied on in estimating the completion of the process. The beginning of transformation was indicated by I per cent of transformation products and the end of transformation by about 99 per cent. The reproducibility of the various methods in the ranges of highest sensitivity was checked by several observations at each time and temperature. The steel used in this investigation was annealed for 24 hr, at 925°C. Macroetching revealed no serious segregation. The specimens for the metallographic and hardness investigations were 1¼ by ½ by ? in. Wires attached to the samples were used for handling. instead of tongs, to avoid chilling. The specimens were heated at 845°C. for ½ hr. and quenched into constant-temperature salt baths held at various temperatures from 205' to 650°C. The time required to transfer the specimens was found to be about 1½ sec., and nearly 5 sec. more was required for them to come to the temperature of the bath. After various lengths of time in the constant-temperature baths the specimens were quenched in water at 2I°C. The specimens were cut in half for the metallographic examination, to provide a surface free from decarburization. To determine the beginning and end of the transformation the percentage of transformation determined metallographically and by hardness was plotted against time. A planimeter was used in the metallographic determination. The hardness and metallographic determinations made at room temperature were confirmed reasonably well by dilatometer measurements taken during the process of transformation at the various temperatures. Two dilatometers were used to

Jan 1, 1942

By Blake M. Loring

RECENTLY the S-curves for 30 to 40 alloy steels have been published.1,2 These steels show individual characteristics, which make each additional S-curve of great interest. There are important differences in the mechanism of the transformation process, the type of transformation product, and the influence of alloying elements. Steels of the same general alloy composition may possess such variable characteristics with regard to the length of time of isothermal transformation that an S-curve for each heat of steel may be desirable. In the present work the isothermal transformation of a steel having the following composition and grain size was studied: 0.20 percent carbon; 0.21 manganese; 0.026 phosphorus; 0.017 sulphur; 0.056 silicon; 1.45 chromium; 3.25 nickel; austenite grain size, 7. The progress of the isothermal transformation was followed by several different methods, including hardness measurements, dilatometer observations, and examinations of the microstructure. It was not expected that these methods would be in precise agreement.3 Accordingly, the changes in microstructure and hardness were given additional weight in determining the initial stage of transformation and the dilatometer measurements were relied on in estimating the completion of the process. The beginning of transformation was indicated by I per cent of transformation products and the end of transformation by about 99 per cent. The reproducibility of the various methods in the ranges of highest sensitivity was checked by several observations at each time and temperature. The steel used in this investigation was annealed for 24 hr. at 925°C. Macroetching revealed no serious segregation. The specimens for the metallographic and hardness investigations were 1 1/4 by 1/2 by 1/8 in. Wires attached to the samples were used for handling, instead of tongs, to avoid chilling. The specimens were heated at 845°C. for 1/2 hr. and quenched into constant-temperature salt baths held at various temperatures from 205° to 650°C. The time required to transfer the specimens was found to be about x 1 1/2 sec., and nearly 5 sec. more was required for them to come to the temperature of the bath. After various lengths of time in the constant-temperature baths the specimens were quenched in water at 21°C. The specimens were cut in half for the metallographic examination, to provide a surface free from decarburization. To determine the beginning and end of the transformation the percentage of transformation determined metallographically and by hardness was plotted against time. A planimeter was used in the metallographic determination. The hardness and metallographic determinations made at room temperature were confirmed reasonably well by dilatometer measurements taken during the process of transformation at the various temperatures. Two dilatometers were used to

Jan 1, 1941

By Hubert D. Keiser

An observation that is finding fresh confirmation in the leadership of the Allied Nations is "When the need arises, a man will rise to fill it." Much the same can be said of industrial advances in the current emergency. Events and circumstances have created needs for new materials and stimulated the inventive genius of man to fill them. The timely development of fibrous-glass manufacture, in relation to present war needs, is a case in point. Historical Summary It is probable that the first glass fibers produced by the hand of man were made about 4000 years ago. Successful production of glass fibers for manifold industrial and military uses, on any scale that could begin to meet present needs, has a history spanning a scant four years. The American processes that brought this young industry into being were developed between the years 1931 and 1937; research and manufacturing efforts were consolidated to create a commercially satisfactory operation as late as November 1939. In the 40 months that have elapsed since then, the industry has achieved commercial importance, supplied immense quantities of materials for pre-war industrial expansion to meet "defense" and Lend-Lease needs, and now has reached such importance that it has come largely under the control of the War Production Board for equitable distribution of its major products among 13 claimant agencies. It is worthy of note, however, that the Bureau of Ships, Navy Department, began exploratory use of fibrous-glass products in 1932, within one year after the date of the first experimental trials of the new process. This early recognition of the military importance of fibrous glass gave impetus to further research work. The foregoing rapid scanning of historical development must be filled in, lest the. impression be created that glass fibers were suddenly created out of thin air, with no antecedent trials, failures, and partial successes. The actual history of glassmaking is lost in antiquity. Probably some nomadic tribesman found molten glass beneath the bed of a hot campfire built upon sand of the proper composition. If his curiosity led him to poke the glowing, viscous pool with a green-wood stick or some handy weapon, it is probable that he drew a glass fiber on the end of his implement. Molten glass has much the same consistency as honey or molasses; it strings out tenuously. Thus, it is quite possible that the first form of glass shaped by man's action was a glass fiber. Artisans in glass, throughout the long Direc- of glassmaking as an art> drew fibers from fine rods for many decorative applications, including "spun glass" decoration in beautiful stemware and the charming millefiori (glass flowers encased in solid glass), and even to create the blood vessels in glass eyes to match a bleary mate.

Jan 1, 1948

By Hubert D. Keiser

An observation that is finding fresh confirmation in the leadership of the Allied Nations is "When the need arises, a man will rise to fill it." Much the same can be said of industrial advances in the current emergency. Events and circumstances have created needs for new materials and stimulated the inventive genius of man to fill them. The timely development of fibrous-glass manufacture, in relation to present war needs, is a case in point. Historical Summary It is probable that the first glass fibers produced by the hand of man were made about 4000 years ago. Successful production of glass fibers for manifold industrial and military uses, on any scale that could begin to meet present needs, has a history spanning a scant four years. The American processes that brought this young industry into being were developed between the years 1931 and 1937; research and manufacturing efforts were consolidated to create a commercially satisfactory operation as late as November 1939. In the 40 months that have elapsed since then, the industry has achieved commercial importance, supplied immense quantities of materials for pre-war industrial expansion to meet "defense" and Lend-Lease needs, and now has reached such importance that it has come largely under the control of the War Production Board for equitable distribution of its major products among 13 claimant agencies. It is worthy of note, however, that the Bureau of Ships, Navy Department, began exploratory use of fibrous-glass products in 1932, within one year after the date of the first experimental trials of the new process. This early recognition of the military importance of fibrous glass gave impetus to further research work. The foregoing rapid scanning of historical development must be filled in, lest the. impression be created that glass fibers were suddenly created out of thin air, with no antecedent trials, failures, and partial successes. The actual history of glassmaking is lost in antiquity. Probably some nomadic tribesman found molten glass beneath the bed of a hot campfire built upon sand of the proper composition. If his curiosity led him to poke the glowing, viscous pool with a green-wood stick or some handy weapon, it is probable that he drew a glass fiber on the end of his implement. Molten glass has much the same consistency as honey or molasses; it strings out tenuously. Thus, it is quite possible that the first form of glass shaped by man's action was a glass fiber. Artisans in glass, throughout the long Direc- of glassmaking as an art> drew fibers from fine rods for many decorative applications, including "spun glass" decoration in beautiful stemware and the charming millefiori (glass flowers encased in solid glass), and even to create the blood vessels in glass eyes to match a bleary mate.

Jan 1, 1948

By Hubert D. Keiser

AN observation that is finding fresh confirmation in the leadership of the Allied Nations is "When the need arises, a man will rise to fill it." Much the same can be said of industrial advances in the current emergency. Events and circumstances have created needs for new materials and stimulated the inventive genius of man to fill them. The timely development of fibrous-glass manufacture, in relation to present war needs, is a case in point. HISTORICAL SUMMARY It is probable that the first glass fibers produced by the hand of man were made about 4000 years ago. Successful production of glass fibers for manifold industrial and military uses, on any scale that could begin to meet present needs, has a history spanning a scant four years. The American processes that brought this young industry into being were developed between the years 1931 and 1937; research and manufacturing efforts were consolidated to create a commercially satisfactory operation as late as November 1939. In the 40 months that have elapsed since then, the industry has achieved commercial importance, supplied immense quantities of materials for pre-war industrial expansion to meet "defense" and Lend-Lease needs, and now has reached such importance that it has come largely under the control of the War Production Board for equitable distribution of its major products among 13 claimant agencies. It is worthy of note, however, that the Bureau of Ships, Navy Department, began exploratory use of fibrous-glass products in 1932, within one year after the date of the first experimental trials of the new process. This early recognition of the military importance of fibrous glass gave impetus to further research work. The foregoing rapid scanning of historical development must be filled in, lest the impression be created that glass fibers were suddenly created out of thin air, with no antecedent trials, failures, and partial successes. The actual history of glassmaking is lost in antiquity. Probably some nomadic tribesman found molten glass beneath the bed of a hot campfire built upon sand of the proper composition. If his curiosity led him to poke the glowing, viscous pool with a green-wood stick or some handy weapon, it is probable that he drew a glass fiber on the end of his implement. Molten glass has much the same consistency as honey or molasses; it strings out tenuously. Thus, it is quite possible that the first form of glass shaped by man's action was a glass fiber. Artisans in glass, throughout the long history of glassmaking as an art, drew fibers from fine rods for many decorative applications, including "spun glass" decoration in beautiful stemware and the charming millefiori (glass flowers encased in solid glass), and even to create the blood vessels in glass eyes to match a bleary mate.

Jan 1, 1943

By C. H. Burgess

ON June 5, 1947, Secretary of State George C. Marshall in a speech at Harvard University outlined a plan for the economic recovery of Europe. The plan contemplated that the United States should provide assistance which would enable the European nations better to help themselves and to help each other to reconstitute from their war-torn lands conditions which would make possible decent standards of living.

Jan 1, 1950