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By J. Wright, R. J. Tyler

Abstract-Changes in the pore structure of hematite pellets during reduction to iron were investigated under a variety of experimental conditions. Pore structures were determined by a mercury penetration technique. The reduction temperature was found to be the major influence on structure, the pore system being bimodal below 750°C and unimodal above 900°C. Pore sizes ranging from 0.04 to 20 [um] were observed in completely metallized pellets produced over the temperature range 650-1050°C. Gas composition and reduction rates also influenced the pore structure of the metallized pellets, although to a lesser extent than the reduction temperature. An apparent activation energy of 24 kcal/mole was derived for the pore formation ptocess.

Jan 8, 1978

By Arthur C. Spencer

In extension of a suggestion already made to account for certain features observed in the Juneau gold-belt in southeastern Alaska,' it is the object of the present paper to indicate in detail certain conditions in which deformation of rocks under their own weight might lead to the production of fractures in which veins could be deposited. A direct, uniformly-distributed pressure of sufficient intensity, applied to an elastic brittle mass offering strung resistance to deformation, produces rupture. In a material of ideal properties the surfaces of rupture under such pressure would be shearing planes inclined at 45' to the line of force, unless there be preliminary deformation, in which case this angle would be greater than 45. This general conclusion, resting upon analytical mechanics, is completely supported by the results obtained by DaubrBe2 in experiments upon the deformation of wax and resin prisms under compression. Let us then first consider one of Daubree's diagrams. In the case illustrated in Fig. 1, four sets of fractures in two approximately right-angled pairs (that is to say, in conjugate sets) were produced by endwise compression of a square cross-sectioned prism. These fractures cut the axis of compression at approximately equal angles, not varying greatly from 45o. The location of the four sets of fractures is obviously determined by the shape of the prism, since the material in each corner acts in a way as a buttress, permitting the bulging to take place most readily on the sides. By limiting the directions in which bulging may take place, results of a more simple nature could be obtained. Take, for instance, a square prism, and place it between two fixed and

Jan 1, 1906

By G. C. Gardner

A new correlation of blast penetration in model and operating blast furnaces is presented which overcomes objections to prevzous correlations. It is shown that the tuyere diameter is only of small importance in determining the magnitude of the penetration. The data from operating furnaces correlate satisfactorily with the data from models whose cross section is a segment of a circle. A bubble-shaped gas space called a "raceway" normally exists in front of the nose of a blastfurnace tuyere. The periphery or "wall" of the raceway is well defined and is composed of densely packed charge particles. The blast. issuing as a jet from the tuyere, entrains gas from the raceway, in the usual manner of a jet, as it flows to the opposing wall. There it divides and flows back around the walls to be entrained once more. The blast must, of course, eventually leave the raceway and pass up through the charge column, but before it does it may, on the average, make several circuits of the kind described and in doing so it carries with it charge particles, which, because of their fast and circulating motion, suggested the name of "raceway". A fuller description of the raceway may be found elsewhere."' Here it is only necessary to mention, in addition, the measurement which characterizes its size. If an iron bar is pushed through the opened peepsight of a tuyere, .as far as it will go with ease, it will be stopped by the relatively impenetrable opposing raceway wall arid the distance that the bar has been pushed from the tuyere nose is called the "penetration". This measurement may be of practical importance and has; been the subject, with considerable success, of several attempts at correlation with other variables2-5 as stated in the next section. There is still, however, a serious objection to the most recent correlation,3 which is overcome by the correlation proposed in this paper. It will be shown that the objection is not trivial, in that the new correlation will attribute considerably different importance to the variables affecting the magnitude of the penetration. The data to be treated were made available by Wagstaff and are the same as those used in his correlation. They include measurements taken on small models, in which a cold air blast was used and no combustion occurred, and they also include data from operating blast furnaces at Wheeling and Fairless. The information from the blast furnaces will be shown to be in substantial agreement with those models whose plan views are segments of a circle and which are thus like segments of a blast furnace. First, Wagstaff's most recent correlation3 will be discussed and the objection will be given. Then the new correlation will be developed and its implications considered. CORRELATION OF J. B. WAGSTAFF Wagstaff's correlation is where and D — the penetration D,-the internal tuyere diameter V —the blast velocity in the tuyere

Jan 1, 1961

By Edmund E. Getzin

Of all the developments in the post-war history of Western Europe, none has been more remarkable in its aims and in the progress it has achieved than the movement toward European integration. It is not an exaggeration to say that this movement marks a virtual revolution, an about-face, in the long and complicated history of European states over the past three centuries. Although sporadic efforts to achieve European integration can be traced back for at least a 100 years, it remained for the breakdown of the European economies as a result of World War II and the subsequent Russian threat to give new impetus to the concept of broader economic and political integration. In fact, the economic integration of Europe following the end of the war was considered so essential that, in 1949, the administrator of the European Cooperation Administration, Paul Hoffman, spoke of the economic integration of Western Europe as an objective of American policy embodied in the Marshall Plan.

Jan 6, 1963

By Orson Cutler Shepard, Charles F. Skinner

THE leaching method that was first widely used with the cyanide process consisted of percolation leaching of crushed ore in vats or leaching tanks. It was frequently necessary to separate the sand for cyanide treatment and discard the slimes, because only granular material allows the necessary amount of solution to percolate through it in a reasonable time. Later a slime process consisting of agitation followed by thickening and filtration was developed, and is extensively used to the present day. Even though the agitation-leaching slime process is considered satisfactory, the cost of plant and of operation are both greater than for a percolation-leaching plant of equal capacity. This situation has been recognized in the hydrometallurgical treatment of copper-bearing slimes; and a considerable amount of work has been done at the Southwest Experiment Station of the U. S. Bureau of Mines in an effort to develop a percolation method of treating slimes. Experimental work on the copper-leaching problem was started by H. E. Keyes1, and later tests were made by J. D. Sullivan and A. P. Towne2. The Bureau of Mines work resulted in the development of a process by which slimes were moisture-agglomerated with sand and crushed ore, to form a permeable mass through which solution could be trickled without breaking down the glomerules. The agglomeration trickle-leaching method was developed on a small scale and finally tried out in a 12-ton vat. Successful results were obtained as long as the leach solution was added slowly, so that the agglomerated charge was never flooded. If the leach solution flooded the charge, the glomerules broke down and the charge became impervious. There are two important difficulties in the application of the agglomeration trickle-leaching method to the cyanide process for gold and silver ores:

Jan 1, 1937

By J. W. Spretnak

It is well-established that decohesions occurring at the interface of the matrix and rigid inclusions and second-phase particles are prime causes of ductile fracture initiation. It is not clear, however, how these decohesions occur. The idea that the interface bond is broken in tension is not particularly attractive when one considers the strength of such interfaces and the fact that plastic flow is not restricted under conditions of continuing flow required to initiate and propagate ductile fracture. A suggestion as to the mechanism of decohesion arises if one takes the position that, as the dislocation density increases with plastic flow and reaches some critical range of density, the phenomenon of flow can be regarded as fluidlike instead of the crystallographic motion of dislocations. As the spacing between dislocations decreases, the matrix becomes increasingly disordered in terms of loss of periodicity. At some critical degree of reduction of the periodicity, it is suggested that flow can be regarded as hydrodynamic, rather than crystallographic. Such a state has been referred to by rheologists as the "plasticized state", or the "fourth state of matter", between the liquid and solid state. A similar argument pertains qualitatively with the increase in equilibrium vacancy concentration as the temperature approaches the melting point. Taking the viewpoint that at larger strains the flow may become hydrodynamic in nature, a mechanism of decohesion is suggested. A well-known phenomenon in boundary-layer flow is that of "separation" locally of the boundary layer from the substrate.' Under certain conditions, the flow in the immediate neighborhood of the substrate becomes reversed, causing the boundary layer to separate from it. The exact condition for separation is that the velocity gradient normal to the substrate vanishes there, or It is of interest that blunt particles such as spheres and circular cylinders are most likely to give rise to separations because of unfavorable pressure distributions behind them. The source cited gives solutions for positions of separations for various geometries. In principle, such separations can also take place when metal is flowing over a "dead zone" of stagnant metal. This may explain the initiation of fracture at the elastic-plastic boundaries of plastic enclaves under a notch.

Jan 1, 1967

Charles Mather MacNeill, President of the Utah Copper CO. and of the Chino Copper Co., and a life member of the Institute since 1899, died at his home in New York on March 17, after a very brief illness with pneumonia. Mr. MacNeill was born at Oak Park, Ill., in 1871, and began his connection with mining enterprises immediately after graduating from high school, his first position being that of cashier with the Pueblo Smelting and Refining Co. He later went to Aspen, Colo., as manager of the Holden lixiviation plant. In 1893, he went to Cripple Creek as manager of the Lawrence Reduction Works, in which Mr. Holden and the late Capt. J. R. DeLamar were large owners. It was at this plant that Mr. Jackling became associated with him. The plant was destroyed by fire and, early in 1894, Mr. MacNeill became associated with Messrs. Spencer Penrose and Charles L. Tutt in a plan to finance and erect a chlorination plant at Colorado City, Colo., for the treatment of Cripple Creek ores. This plant was erected and was known as the Colorado-Philadelphia Reduction Works. Mr. MacNeill was general manager of the plant, Mr. Tutt having been president and Mr. Penrose, secretary and treasurer. The plant was very successful and was expanded, hally being reorganized under the name of the United States Reduction & Refining Company. Late in 1903, or very early in 1904, D. C. Jackling called the attention of Messrs. MacNeill and Penrose to the copper properties in Bingham Cañon, Utah, which have since become the main properties of the Utah Copper Co. After extended examinations and milling tests, these properties were bought, Mr. MacNeill becoming president of the Utah Copper Co., Mr. Penrose, secretary-treasurer, and Mr. Jackling, general manager. Mr. MacNeill remained president of the company to the time of his death. Mr. MacNeill was also a director, a member of the executive committee, and was largely interested in the Ray Consolidated Copper Co.; he was also president and a member of the executive committee of the Chino Copper Co. He had a variety of other mining interests, but the ones mentioned were distinctly the meost important. He was a director

Jan 1, 1923

By R. L. Langenheim

Cooperative education for engineers is based on the premise that theory and practice are inseparable in training men for the engineering profession, and the two must be advanced simultaneously in order to train men most successfully and efficiently. The teaching of theory obviously should be done by the college but the practice must be obtained in the field where the application of the theory is made. The ideally trained engineer is one that knows theory, can apply the theory to practice, can direct, and work with, his fellow men. The old four-year plan of training engineers does a fair job of teaching the underlying theory of engineering but neglects entirely the training necessary for application of the theory, except through laboratory experiments, and the training in adjustments necessary to direct and work with men. An engineer, like a lawyer, doctor, dentist or other professionally trained man, cannot practice until he has had practical experiences that give him a knowledge of the other phases of his profession. The doctor serves as an interne, the lawyer reads law in the office of a practicing attorney, and the engineer must enter the profession as a laborer or as an apprentice, unless he has had the advantage of a cooperative education. Cooperative education provides the opportunity for the coordination of practical and theoretical training for the engineering profession throughout the period of training and thus eliminates many that are unfit to enter the profession, giving them an opportunity to seek other fields for which they may be better fitted, and reduces the overhead in industry that results from a large turnover of men not fitted for the profession. The Cooperative Plan Cooperative education in engineering is no longer an experiment. It was inaugurated at the University of Cincinnati in 1904 by Dean Herman Schneider, and has worked successfully ever since. Over twenty schools offer this type of education and many thousands of young men have had the opportunity to receive their technical training under this plan. Under the cooperative plan a student attends class for a period of eight weeks, then enters industry for eight weeks, maintaining this schedule

Jan 1, 1937

Charles Mather MacNeill, President of the Utah Copper CO. and of the Chino Copper Co., and a life member of the Institute since 1899, died at his home in New York on March 17, after a very brief illness with pneumonia. Mr. MacNeill was born at Oak Park, Ill., in 1871, and began his connection with mining enterprises immediately after graduating from high school, his first position being that of cashier with the Pueblo Smelting and Refining Co. He later went to Aspen, Colo., as manager of the Holden lixiviation plant. In 1893, he went to Cripple Creek as manager of the Lawrence Reduction Works, in which Mr. Holden and the late Capt. J. R. DeLamar were large owners. It was at this plant that Mr. Jackling became associated with him. The plant was destroyed by fire and, early in 1894, Mr. MacNeill became associated with Messrs. Spencer Penrose and Charles L. Tutt in a plan to finance and erect a chlorination plant at Colorado City, Colo., for the treatment of Cripple Creek ores. This plant was erected and was known as the Colorado-Philadelphia Reduction Works. Mr. MacNeill was general manager of the plant, Mr. Tutt having been president and Mr. Penrose, secretary and treasurer. The plant was very successful and was expanded, hally being reorganized under the name of the United States Reduction & Refining Company. Late in 1903, or very early in 1904, D. C. Jackling called the attention of Messrs. MacNeill and Penrose to the copper properties in Bingham Cañon, Utah, which have since become the main properties of the Utah Copper Co. After extended examinations and milling tests, these properties were bought, Mr. MacNeill becoming president of the Utah Copper Co., Mr. Penrose, secretary-treasurer, and Mr. Jackling, general manager. Mr. MacNeill remained president of the company to the time of his death. Mr. MacNeill was also a director, a member of the executive committee, and was largely interested in the Ray Consolidated Copper Co.; he was also president and a member of the executive committee of the Chino Copper Co. He had a variety of other mining interests, but the ones mentioned were distinctly the meost important. He was a director

Jan 1, 1923

By R. W. Callen, W. A. Hockings

This paper describes a computer program which calculates material balances for complex steady-state material flow circuits encountered in mineral processing. The program determines mass flows in the various process streams of a flowsheet from multicomponent analytical data obtained from samples of the streams. The program, Metallurgical Balance System (MBS), has been used extensively in treating Pilot plant test data, in production evaluation and control, and in plant design. The program performs well even on ill-conditioned data. Input to the program is easily accomplished by unskilled personnel and the output appears in well-formatted tables.

Jan 1, 1981

By Dart Wantland, C. A. Heiland

There once was a little kid, whose lot was a very tough one until he grew up. His parents did not have much in common; from all indications, it is probable that the child was not wanted. His father Geology and his mother Physics separated shortly after his birth, which occurred during the World War amid a smoke screen of mathematics. He was kicked around a great deal. His parents could not agree on a name, and they finally christened him "Geophysics," for short. His relatives insisted that the name should be "Geophysical Prospecting," "Geophysical Exploration" or "Exploratory Geophysics"; though the youngster has grown up by now, this battle is still going on. His father did not think the child would amount to much until he began to show some unexpected talents, which were acquired, no doubt, from his mother Physics. His progress caused his father no little worry, and he began to wonder whether his offspring would help him in his business when he grew up or would set up shop in competition with the old man. His aunt Petroleum watched his growth with benevolent interest; his uncle Mining remained rather skeptical and cousin Civil Engineering not only assumed the attitude of the man from Missouri but was not much convinced even after he had been shown. Making a long story short, the kid decided that he had to stand on his own feet and get along as best he could. Having come from a good family he possessed some outstanding characteristics such as resourcefulness and a reasonable amount of business ability. He therefore decided that it would be to his advantage to follow in his father's and mother's footsteps as much as possible, and develop the good qualities of both. As a result, the youngster did fairly well for himself, and his relatives decided that it might be to their advantage to be on better terms with him. Father Geology had come to the conclusion that the boy could be very helpful to him and now wanted him to live in his house. His mother, who had brought him through the teething and measles stages, felt quite capable of bringing up the boy without the help of his father; and, as the fairer sex will do, would confide to a neighbor every now and then that his

Jan 1, 1940

By C. A. Heiland, Dart Wantland

There once was a little kid, whose lot was a very tough one until he grew up. His parents did not have much in common; from all indications, it is probable that the child was not wanted. His father Geology and his mother Physics separated shortly after his birth, which occurred during the World War amid a smoke screen of mathematics. He was kicked around a great deal. His parents could not agree on a name, and they finally christened him "Geophysics," for short. His relatives insisted that the name should be "Geophysical Prospecting," "Geophysical Exploration" or "Exploratory Geophysics"; though the youngster has grown up by now, this battle is still going on. His father did not think the child would amount to much until he began to show some unexpected talents, which were acquired, no doubt, from his mother Physics. His progress caused his father no little worry, and he began to wonder whether his offspring would help him in his business when he grew up or would set up shop in competition with the old man. His aunt Petroleum watched his growth with benevolent interest; his uncle Mining remained rather skeptical and cousin Civil Engineering not only assumed the attitude of the man from Missouri but was not much convinced even after he had been shown. Making a long story short, the kid decided that he had to stand on his own feet and get along as best he could. Having come from a good family he possessed some outstanding characteristics such as resourcefulness and a reasonable amount of business ability. He therefore decided that it would be to his advantage to follow in his father's and mother's footsteps as much as possible, and develop the good qualities of both. As a result, the youngster did fairly well for himself, and his relatives decided that it might be to their advantage to be on better terms with him. Father Geology had come to the conclusion that the boy could be very helpful to him and now wanted him to live in his house. His mother, who had brought him through the teething and measles stages, felt quite capable of bringing up the boy without the help of his father; and, as the fairer sex will do, would confide to a neighbor every now and then that his

Jan 1, 1940

By Donald F. Kennedy

During the past several years Climax Molybdenum Co. has been engaged in testing various types and sizes of hollow drill steel. The majority of tests have been on 7/8-in. hexagon st.ee1, inasmuch as it represents approximately 70% of total drill steel consumption at the Climax operation. Prior to December 1960, tests on 7/8-in. hexagon drill steel were conducted on steel with a forged collar and, in most cases, with a threaded bit connection. Through these tests and research, some improvement in steel life was achieved by making changes in heat treatment, design and alloying constituents. However, during that month, research and testing commenced on a rubber collar which was designed to replace the forged collar on 7/8-in. hexagon drill steel. Manufactured by the LeRoi Div. of Westinghouse Air Brake Co.. the collar. is very simple in design, consisting of a 1 ½ -in. diam steel cylindrical sleeve 2 in. long, containing a bonded rubber insert and attached to the steel with an epoxy cement

Jan 8, 1962

By C. D. Rubert, W. J. Parton

LARGE quantities of fine anthracite with associated impurities are discharged with the waste water from the coal-cleaning plants in the Pennsylvania anthracite region. Furthermore, for many years this fine material has accumulated and formed silt banks. The difficulty of removing the impurities from the fine material and the lack of adequate markets are responsible for the waste of this material. In view of a larger demand for fine coal, mainly for pulverized fuel, the Lehigh Navigation Coal Co. Inc. decided to investigate the froth flotation process for recovery of fine coal from these waste solids. A test plant was constructed and operated for six months during 1942 in order to determine the practicability of recovering coal from the waste water of a cleaning plant (breaker) by froth flotation, and to obtain operating data for designing a commercial plant if the results were favorable. PRELIMINARY INVESTIGATION Before the pilot plant was constructed information was obtained by field and small-scale laboratory tests to serve as a guide in the design and operation of the pilot plant. Size and ash analyses of a representative sample of the material discharged in the wash water from a cleaning plant are given in Table I. [ ] The refuse content increases progressively as the size of the particles decreases. The larger particles (+35 m.) are low in ash content and could be marketed without cleaning. Since these solids are discharged from the breakers with 90 to 95 per cent water by weight, the first step in the recovery of the coal was that of reducing the quantity of water so that water in excess will not have to be handled. Furthermore, it was found that the removal of most of the minus 200 mesh high-ash material was desirable to permit the most efficient flotation of the coal. Classification tests were run and showed that a hydroseparator overflow rate of 12 ft. per hour was sufficient to eliminate much of the minus 200-mesh material while allowing the coarser material to settle and be thickened.

Jan 1, 1944

By P. A. Beck, W. D. Manly

In a recent note Sully and Head1 showed that the Cr-Fe sigma phase is isomorplious with the Cr-Co gamma phase, and that the lattice constants are also nearly identical. In a preliminary investigation of the ternary Cr-Co-Fe system at 800°C at this laboratory the above findings were confirmed, and it was found by microscopic techniques, using various etching reagents, that the two binary phases form an urinterrupted series of solid solutions with each other. These solid solutions occupy a straight narrow band which cuts across the 800°C isothermal section of the ternary system, connecting the two binary phases. A detailed investigation of the Cr-Co-Ni ternary system at 1200°C disclosed that here, too, the Cr-Co gamma phase extends deep into the ternary system in the form of a long narrow lip. The fact that this sigma type lattice is sustained even when well over half of the Co atoms in it are replaced by Ni atoms, with relatively little change in the Cr content, clearly indicates that Ni itself has a certain tendency to form the sigma phase with chromium. This tendency is hidden in the binary Cr-Ni alloys, where the sigma phase is not known to occur, but it becomes operative in the presence of a suficient amount of Co. The interpretation of these facts in terms of electron concentrations is rendered difficult by the uncertainty of our present knowledge of the valency electron structure of the transition elements in their alloys. However, Sully and Heal's results and the present work suggest that intermetallic phases with signla type lattice may occur more frequently in these little investigated alloys than heretofore suspected. In particular, it is expected that a similar phase may exist in the V-Co and perhaps in the V-Ni system, in analogy to the known sigma type phase in the V-Fe system, and that all these sigma type phases may form extensive solid solutions with one another.

Jan 1, 1950

By Robert C. Weed

Leaching in place at Cananea began in the 1920's on a limited scale. The first plants were small wooden boxes located underground in the Capote and Oversight mines, and output was low. Scrap iron was used as precipitant. Later several other small plants were started up. Leaching was limited entirely to underground areas, and production remained low. The Veta precipitating plant, the first on a larger scale, was put into operation in the late 1920's. After a period of intermittent service it was rebuilt in 1946 and has since been running continuously.

Jul 1, 1956

Horace F. Lunt, York, Montana* :—Two years ago I visited the region described by Mr. Jennings and assisted in the examination of a somewhat similar group of deposits in the White Mesa sandstone on the Navajo Indian Reservation, 125 miles north of Flagstaff and 50 miles east of the Kaibab plateau. There, the Triassic red sandstone is less than 200 ft. thick, and is overlain by a stratum from 200 to 250 ft. thick of white sandstone, which gives the name of " White Mesa" to that locality. The white sandstone shows all phases of crossbedding in great complexity, and evidently marks a period of oscillation and subsidence of the water, or an elevation of the land, at the close of a geological epoch. The prevailing color is white or gray, but occasionally it is red. In structure, it is composed of well-worn grains of quartzsand, from which most of the cementing material has been leached out, leaving it soft and friable. Possibly the cement was ferruginous, as is indicated by occasional traces of red color. The copper-deposits consist of a replacement of the cement of one particular cross-bedded stratum of the sandstone by chrysocolla, having also at times various quantities of tenorite in grains or masses. Some specimens of the ore contain as much as 32 per cent. of copper. Generally the copper-deposits are a few hundred cubic feet in size, and no strict line of demarcation is shown between them and the surrounding sandstone, the bluish-green color of the chrysocolla gradually fading into the white of the sandstone. The ore is apparently associated with small vertical crevices or fissures. Some of the deposits show a distinct vein-structure, while others do not. The origin of the ore is not very clear. Undoubtedly the solutions, coursing through the crevices noted above, played a prominent part in its deposition, as possibly

Jan 1, 1904

By Thomas D. West

A short time ago, I had occasion to cast iron plates 1 in. thick, direct from metal containing Si, 0.51; 8, 0.045; Mn, 0.75; and P, 0.094 per cent. Much to my astonishment, I found that there was no trouble in planing them; whereas, if cupolaimetal of like composition had been used,*the planing would have been a difficult operation. I have often noticed a greater fluidity or " life " in furnace-metal, as compared with the cupola-product. Iron can be seen flowing down the furnace-runners from 50 to 100 ft., and reaching the last pig-bed in satisfactory condition, while cupola-metal might have solidified before it had flowed so far. I have seen Bessemer iron, which, on account of its low phosphorus-content, does not have the " life " of ordinary foundry-iron, held in a 30-ton ladle for nearly an hour and a half; and after skimming off the coke-dust, it still had to be cooled off' considerably before being cast. As a general proposition, it is known that the lower sulphur-content and the frequently higher temperature of direct-metal, compared with the same iron remelted in the cupola, has much to do with its greater life; yet some problems connected with this phenomenon seem to call for further study. For instance, furnace-metal containing more than 1 per cent. of silicon holds carbon, which is separated later as "kish." This separation does not take place to any great degree while the metal is very hot; but during its gradual cooling, at times, the kish is given off in such large quantities as to cover the ground from 20 to 30 ft. around the ladle. In making castings of direct-metal, especially with a high content of silicon, the separation of kish becomes an annoyance. Perhaps this throwing out of the excess of carbon makes the life of the metal shorter, after it has been remelted in a

Jan 1, 1905

By B. E. Thompson, H. B. Fuqua

The area discussed herein, commonly known as the North Texas district, embraces the following 10 counties: Archer, Baylor, Clay, Cooke, Foard, Hardeman, Knox, Montague, Wichita and Wilbarger. It is underlain by two major structural features. The northernmost portion of the district, including Coolie, Montague, northern Clay, Wichita, Wilbarger, Foard and Hardeman Counties, is underlain by the system of buried mountains known as the Red River uplift, which is parallel to and closely related to the Wichita-Amarillo uplift of Oklahoma and the Texas Panhandle. While the presence of a great majority of the numerous oil fields of the area is traceable to this feature, the production in Archer, southwestern Clay and southeastern Baylor Counties is due to the influence of what is known as the Cisco arch (so called because of its influence on Cisco deposition), the axis of which extends in a northwest-southeast direction across southwestern Wichita County into Archer County. Developments during 1938 Important discoveries in the district were considerably more numerous and of more economic importance than for several years. In addition to a number of small, relatively unimportant discoveries and to the usual local extensions to the various producing fields in the several counties, at least eight fields, most of them apparently of considerable areal extent and importance, were found. The Helmerich and Payne, Incorporated and Blackwell Oil and Gas Company No. 1 Wilson. 4 miles southeast of the town of Holliday, in north central Archer County, encountered a pay of Strawn age at a depth of 3841 to 3858 ft., and was completed for an initial production of 1952 bbl. T'his well opened a new deep pool in the K. M. A. producing zone 8 miles southeast of the K. M. A. production. Subsequently an additional deeper horizon, also of lowcr Strawn age, was discovered by wells that failed to yield commerecial oil from the horizon of the discovery well.

Jan 1, 1939

By J. L. Gregg

A study of copper-base and silver-base alloys was made with the object of finding, if possible, useful alloys subject to dispersion hardening. These studies led to the discovery of several alloys showing considerable dispersion hardening, the most important of which, the alloys of copper with iron, nickel, cobalt and chromium silicides, have since been very ably reported by M. G. Corson.l This paper is offered as a few notes covering alloys other than those described by Corson and some further data on the silicide alloys. Copper Alloys For the purpose of making a rapid survey of copper alloys that might show useful dispersion-hardening phenomena, various alloys were prepared containing 3 per cent. of additional elements added in such proportion that possible compounds could be formed without an excess of either added element. These alloys in the form of rolled or forged pieces were quenched in water from a temperature of 871" C. (1800" F.) and subsequently aged at various lower temperatures for l-hr. periods. The comparison of the Rockwell hardness of the quenched alloys with the maximum hardness of the alloys after aging was used as a measure of the dispersion hardening. Table 1 shows the Rockwell "E" hardness 1/8-in. ball, 100-kg. load) of the quenched alloys, together with the maximum hardness resulting from aging. The reheating temperature given in this table is the aging temperature at which maximum hardness resulted from a l-hr. sojourn. From this table it may be observed that only the silicide alloys showed significant dispersion hardening. Of these, the only one not described by Corson is the Cu-Be-Si alloy. This alloy contained 1.35 per cent. beryllium and 1.78 per cent. silicon, which is approximately equivalent to 3 per cent. Be2Si. It had a yellow color and scaled much less than the other silicide alloys upon heating. It could be worked easily either hot or cold but hardened very rapidly on cold working. The annealed alloy upon drawing from a diameter

Jan 1, 1929