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By J. L. Brimhall

Slip-line formation during bending has been studied on neutron-irradiated molybdenum single crystals. For equivalent strains, the slip lines are coarse and distinct in the irradiated molybdenum and not resolvable in the unirradiated molybdenum. The slip lines have been directly correlated with dislocation channels present in the irradiated and deformed thin foils. The heterogeneous distribution of the dislocations during deformation in the irradiated material results from dislocation interaction with the dejects produced during irradiation. Impurities , in the form of' carbides, affected the dislocation channeling Principally by acting as dislocation sources. ALTHOUGH the mechanical behavior of irradiated materials has been studied extensively, the precise mechanism of irradiation hardening has not been established. Some information on the microstructural species responsible for hardening of irradiated materials has been derived from direct and indirect observations. The direct observation of the structure of deformed irradiated metals, particularly by transmission electron microscopy, is a relatively new and unexplored area. Slip-line studies in fcc metals have been restricted primarily to copper.1-3 Very coarse slip lines, representing slip on many closely spaced planes, have been observed in deformed, irradiated copper. Coarse slip lines have also been observed in irradiated aluminum.4 Clear channels in irradiated copper caused by dislocation motion through the defect structure have been seen by transmission electron microscopy and correlated with slip lines.5-6 To date, little work has been reported on the irradiated bcc metals. Eyre described the slip lines around hardness indentations on irradiated iron and found them to be more distinct than lines in unirradiated material.' Mastel et al.' have observed channels in deformed irradiated molybdenum similar to those reported in copper. As part of a program concerned with the effect of neutron irradiation on metals, the slip-line

Jan 1, 1965

By P. S. Rudman

The solubility limit and the diffusivity of carbon in molybdenum have been obtained by duffising carbon into molybdenum rods from a Mo + Mo2C powder mixture. The solubility limit was taken as the long-time asymptotic limit of the rod composition. The diffusiv-ity was obtained from fractionally saturated rods from the rate of change of the average composition. Compositions were determined by chemical analysis. The solubility limit obtained is: WhILE the Mo-C system is important in refractory alloy technology neither the solubility limit nor the diffusivity of carbon in molybdenum is unambiguously known. In Fig. 1 the Mo-C phase diagram is presented. The heavy lines, the terminal solution solubility limit, and the eutectic temperature are results of the present investigation and will be discussed in detail later. However, it is readily seen that the previously published solubility limit determinations, Few and Manning1 and Fromm and ROy2 differ by up to an order of magnitude. The general form of Fig. 1, the Mo2C field, and a eu- tectic temperature -2200°C are due to an early Investigation by Sykes et a1.3 Although they did not determine the solubility limit, they did establish that the maximum at the eutectic temperature was about 1000 ppm. The only other prior data found on the solubility limit is from a lattice-parameter study by Speiser et a1 .,4 from which it can be concluded that the maximum solubility is greater than 1800 ppm. There does not appear to be any data oh the diffusivity of carbon in molybdenum. However, Samsonov and Epik5 have determined, from the rate of growth of an MozC layer, the diffusivity of carbon in Mo2C, and this has been erroneously interpreted, for example by ~c~eil,' as applicable to diffusion of carbon in molybdenum.

Jan 1, 1968

By A. R. T. Denues

LIQUID-OXYGEN explosives commonly consist of a carbonaceous absorbent enclosed in a canvas wrapper and soaked with a liquid containing more than 90 mol per cent of oxygen. Investigation of these explosives in this country was initiated in 1917 by George S. Rice, then Chief Mining Engineer of the Bureau of Mines. The early development is summarized in two papers.1,2 Their characteristics, advantages and disadvantages were considered in a recent bulletin of the Bureau of Mines.,3 Other publications of this Bureau4, 5 treat the technology of these explosives and contain adequate references to pertinent literature. These investigations defined the properties of liquid-oxygen explosives and improved them greatly; however, an outstanding disadvantage is their high inflammability, a property of critical practical importance. These explosives as hitherto prepared are easily inflamed; the combustion resulting from an accidental ignition is particularly dangerous because of the ease with which it passes into detonation. For this reason the Bureau of Mines undertook a cooperative investigation, which has resulted in the development of fire-retardant treatment for the minimization or elimination of this hazard without materially impairing the explosive properties, including the ease of detonation. This presentation will offer a general description of the investigation and the outstanding results. Further phases will appear in subsequent short papers, and the entire investigation including the results of detailed experiments will be available in a forthcoming bulletin of the Bureau of Mines (Bull. 429). The effects produced by fire-retardant treatments of the carbonaceous absorbent and of the canvas wrappers were investigated separately, and the efficacy of combinations of these treatments with particular reference to the possibility of inflammation and to the development of detonation from inflammation was studied. The experimental explosive was pre¬pared from a granular carbonaceous absorbent and. the results described maybe more or less unique for such a material. An extensive preliminary

Jan 1, 1940

W. G. MITCHELL,* New York, N. Y.-I quite agree with Mr. Wilson1 in the statement that the Bonanza copper orebodies of the Jerome District are definitely pre-Cambrian. You might go much further than that. It is an interesting fact and, I think, well substantiated that the chalcocite enrichment is pre-Cambrian, and in that particular the deposits are unique, so far as I know, among copper-ore deposits. It is certainly true, under my scheme of classification, at least, and I think it has been supported by the work of Mr. Reber of the United Verde Extension, that chalcocitization was entirely accomplished prior to the laying down of the Cambrian sediments. The statement of Mr. Wilson that no Yavapai schist, as defined by Jagger and Palache, has been found in the Jerome District and that the schist in Jerome is composed entirely of ancient intrusive and extrusive volcanic rocks and bedded tuffs is one with which I am not entirely in accord. I believe that it is true that the schists at Jerome are largely composed of bedded volcanic material, I am also certain that there is a considerable proportion of plastic material in those schists. I have seen a good many slides, and it is quite common to find quartzites and limestones in the schists. At a short distance from Jerome, at the Arizona Binghamton, there are limestone strata in the schists several feet in thickness, and unmistakably a part of the original sediments as laid down. Another statement of Mr. Wilson is supported by my own observations. In the United Verde mine included fragments of sulfide ore are found in later anthracite dikes, which cut the orebodies but do not invade the chalcocite sediments. This is not only true, but those fragments of sulfide ore that are of small size, from the size of a walnut to fragments 2 and 3 ft. in diameter, are of the original unenriched pyritic material. I have never found high-grade ore, either chalcopyrite or chalcocite, in any of those dikes.

Jan 4, 1919

By B. J. Yamada, D. W. Fuerstenau

Long-chained neutral molecules (decyl alcohol) increase the flotation of corundum with sodium dodecylsulfate and trimethyldodecylammonium chloride as collectors. This phenomenon is postulated to result from coadsorption of the neutral molecules with the collector ions. Flotation and streaming potential experiments have shown that sodium laurate is an effective collector for corundum at more dilute concentrations than sodium dodecylsulfate or sulfonate.1>2 It has been postulated that this phenomenon results from the adsorption of both laurate ions and lauric acid molecules, whereas sodium dodecylsulfate can be adsorbed only as dodecylsulfate ions, since this collector does not hydrolyze under flotation conditions. Similar effects have been observed in alkaline solutions with dodecylammonium chloride and trimethyldodecylammonium chloride as collectors.' If in- creased flotation occurs with the collectors which hydrolyze because of adsorption of the neutral molecules, purposeful addition of long-chained molecules should increase the flotation rate of minerals with such collectors as sodium dodecylsulfate or trimethyldodecylammonium chloride because these long-chained molecules should coadsorb with the collector ions. The effect of neutral molecules on flotation in these cases must depend on an adsorption mechanism which differs from that proposed by Cook for the adsorption of xanthic acid molecules by galena. For neutral molecules to function as collectors in the flotation of insoluble oxide minerals, adsorption of organic ions must first occur to provide a means of anchoring the fatty acid or amine molecules. Without adsorption of collector ions, flotation does not occur even in the presence of large quantities of neutral molecules, as is indicated by the cessation of flotation at low pH values with soaps as collectors or at high pH values with primary amine salts as collectors.' Neutral molecules, such as fatty acids, must be adsorbed through van der Waals attraction between the hydrocarbon chains of the adsorbed soap ions and the hydrocarbon chains of the fatty acid molecules. The mutual association of hydrocarbon chains results

Jan 1, 1962

By A. S. Nowick, A. E. Roswell

Anelastic measurements of atomic mobility in an Ag-Zn substitutional solid solution, make possible a study of the rate of decay of lattice defects frozen into the alloy by quenching. A WIDE variety of experimental evidence has accumulated recently in support of the belief that atomic mobility or diffusion in face-centered cubic lattices occurs principally through the movement of lattice defects, as contrasted to a mechanism by which two or more atoms directly exchange lattice positions. The most direct evidence, summarized in a recent review,' includes the Kirkendall-effect measurements and anelastic measurements on quenched alloys. Theoretical calculations' have focused attention on the lattice vacancy as the defect probably responsible for diffusion in the common metals. Later calculations3 have also shown the possible importance of combined pairs of vacancies in producing diffusion. The only defect that has been considered seriously, in addition to the vacancy and combination of vacancies, is the "interstitialcy" (an atom which has left its normal lattice position and entered an interstitial position) ; the calculated energy of formation of an interstitialcy in a close-packed lattice is too large to permit a reasonable probability for the occurrence of this defect In view of these calculations it may be tentatively concluded that the defects producing atomic movements are single or multiple vacancies. Anelastic measurements of atomic mobility in substitutional solid solutions provide a valuable method for the study of lattice defects. By means of this method it was first demonstrated' that defects may be frozen into a lattice by rapid quenching from high temperatures. (It was subsequently shown6 that resistivity measurements may also be capable of detecting the presence of frozen-in defects.) A summary of the principles involved in these anelastic measurements will now be presented. The anelastic method is based on a relaxation phenomenon in substitutional solid solutions, first discovered by Zenera in a brass and subseauentlv investigated extensively in a series of Ag-zn solid solutions.' This relaxation effect may be observed in the usual way either dynamically, as a peak in

Jan 1, 1954

By Carl Belser

This paper summarizes the data on the oil-shale deposits of western Colorado, Utah and Wyoming. It is based on published reports by the U. S. Geological Survey, on the results of core drilling and sampling by the Bureau of Mines, on the drill cuttings from the Genera1 Petroleum well, on a recent unpublished report by the Geological Survey on the geology of Naval Oil-Shale Reserves No. I and No' 21 and from information supplied by geologists of private companies who have investigated the Green River formation. The paper also contains a revised estimate of the grade and tonnage of minable thicknesses of oil shale of western Colorado. Introduction The oil shales of the Green River formation of Colorado, Utah and Wyoming comprise an important natural resource for the production of synthetic liquid fuels. The oil shale in western Colorado generally is more amenable to exploitation, apparently richer, and probably more persistent than in Utah or Wyoming. Work is now being done by the Bureau of Mines near Rifle, Cola. to ascertain the best procedures for mining the oil shale, producing shale oil from the oil shale, and converting the oil into more salable products. As a part of this program, holes were drilled and cores were taken of the oil shale on Naval Oil-Shale Reserve No. I. In addi- tion, drill cuttings were obtained from a well drilled through the Green River formation by the General Petroleum Co. about 18 miles northerly of the Naval Oil-Shale Reserve. Geology During middle Eocene time a broad, shallow body of water, now called Uinta Lake, covered northwestern Colorado and east-central Utah; a similar lake, known as Gosiute Lake, was in southwestern Wyoming Each of these contemporary lakes was bounded by high hills; the drainage was to the south. The Green River formation was laid down as sediments in the bottoms of these lakes. It is 3000 ft thick and has been divided into the following four members:

Jan 1, 1949

By B. F. Fackenthall

The Durham Iron Works of Messrs. Cooper & Hewitt, near Riegelsville, Pa., occupy a site which has been almost continuously the scene of iron-manufacturing industry since 1727. Doubtless if Anthony Morris and his thirteen associates, who in that year erected a blast-furnace on the Durham Creek, a short distance above where the Durham Iron Works now stands, could have had a vision of the improved and enlarged apparatus of their successors, they would have been not less astonished by the huge stack, the hot-blast ovens, and the blowing-engines of the modern blast-furnace, than by the railroad which now follows the bank of the river on which their clumsy " Durham boats " once floated pig-iron to Philadelphia. In one particular, posterity must confess their snperiority. We are told that in November, 1728, they shipped three tons of Durham iron to England. The proprietors of the Durham Iron Works are not now shipping iron to England. The present Durham furnace was built (in place of two smaller ones) in 1874 and 1875, and made its first blast in 1876. A description of it, with other works of the same proprietors, at Trenton, N. J., by A. L. Holley and Lenox Smith, was published in London Engineering for January 31st, and February 21st, 1879. Since that time, a number of improvements, dictated by experience, have been made in the details of the furnace and fittings; and the recent roilclusion of a long and successful blast presents a convenient opportunity for a description of the works and a statement of the results of practice. The accompanying drawings will show the general arrangement of the works. The furnace, Plate I., Figs. 1 and 2, is 75 feet high by 19 feet bosh. The hearth is 11 feet 4 inches in diameter, with seven tuyeres 5 feet 6 inches above hearth-line. The tuyeres project 9 inches into the furnace, making the interior tuyere-circle 9 feet 10 inches in diameter. The front is a modification of Luermaun's

Jan 1, 1886

By A. R. T. Denues

LIQUID-OXYGEN explosives commonly consist of a carbonaceous absorbent enclosed in a canvas wrapper and soaked with a liquid con-taining more than 90 mol per cent of oxygen. Investigation of these explosives in this country was initiated in 1917 by George S. Rice, then Chief Mining Engineer of the Bureau of Mines. The early development is summarized in two papers.1,2 Their characteristics, advantages and disadvantages were considered in a recent bulletin of the Bureau of Mines.3 Other publications of this Bureau4,5 treat the technology of these explosives and contain adequate references to pertinent literature. These investigations defined the properties of liquid-oxygen explosives and improved them greatly; however, an outstanding disadvantage is their high inflammability, a property of critical practical importance. These explosives as hitherto prepared are easily inflamed; the combustion resulting from an accidental ignition is particularly dangerous because of the ease with which it passes into detonation. For this reason the Bureau of Mines undertook a cooperative investigation, which has resulted in the development of fire-retardant treatment for the minimiza-tion or elimination of this hazard without materially impairing the explosive properties, including the ease of detonation. This presentation will offer a general description of the investigation and the outstanding results. Further phases will appear in subsequent short papers, and the entire investigation including the results of detailed experiments will be available in a forthcoming bulletin of the Bureau of Mines (Bull. 429). The effects produced by fire-retardant treatments of the carbonaceous absorbent and of the canvas wrappers were investigated separately, and the efficacy of combinations of these treatments with particular reference to the possibility of inflammation and to the development of detonation from inflammation was studied. The experimental explosive was pre-pared from a granular carbonaceous absorbent and the results described may be more or less unique for such a material. An extensive preliminary

Jan 1, 1940

By Earl Oliver

This paper is based on the formula that the petroleum industry is sick—find the cause, eliminate it, and the industry will get well. There is perhaps no difference of opinion that the cause is overproduction, actual or potential. But that, again, is a result rather than a cause. The problem is to study the influences that serve to keep production and consumption out of balance. Production control is a popular theme and a natural one at this time when the whole world is unstable; but production control in its popular sense means little more than the application of emergency measures while danger threatens. Economists differ as to the effectiveness of these, most of which are designed to alleviate and not to cure, but we assume there are none who question the wisdom of promoting conditions under which economic forces are permitted to operate freely in bringing about stable conditions. The petroleum industry suffers from two classes of economic ills that serve to promote overproduction; namely, those which are common to all industries and those which are peculiar to this industry. It is of the latter I wish to speak. Strange to say, government is responsible in large part for this latter class of ills that affect the petroleum industry and we are coming to recognize that only through the assistance of government can they be corrected. Instability of the petroleunl industry, in so far as human agency was involved, had its inception in 1875 when a Pennsylvania jurist, called upon to make a decision for which there was no precedent and fancying he noted some resemblance between the so-called fugitive nature of oil and gas and that of wild game, made mention of that resemblance. Other courts being impressed by the analogy enlarged upon it, and gradually fixed upon oil and gas a legal status in certain important respects similar to that of wild game. Although later the courts abandoned this analogy, certain practices that developed out of that early concept have continued to this day and are largely responsible for the industry's present plight. Thus, instead of ownership in place that is characteristic of private property generally, the law of capture was applied to oil and gas. Now, the rapid and wasteful depletion of game

Jan 1, 1932

By I. C. White, G. H. Ashley, J. A. Bownocker

Among the rich mineral deposits of the great Appalachian field, the Pittsburgh coal bed stands pre-eminent. Other coal beds may cover a wider area, or extend with greater persistence, but none surpasses the Pittsburgh seam in economic importance and value. It was well named by Rogers, and his able assistants of the First Geological Survey of Pennsylvania, in honor of the city to whose industrial growth and supremacy it has contributed so much. Whether or not the prophetic eye of that able geologist ever comprehended fully the part which this coal bed was to play in the future history of the city that gave it a name we do not know; but certain it is that the 7 ft. of fossil fuel, which, in Rogers' time, circled in a long black band around the hills and, overlooking the site of Pittsburgh from an elevation of 400 ft. above the water of the Allegheny and Monongahela, extended up the latter stream in an unbroken sheet for a distance of 200 miles, has been the most potent factor in that wonderful modern growth that has made the Pittsburgh district the manufacturing center of America, and that bids fair to continue until it shall surpass every other district in the world, even if it does not now hold such primacy.' The Pittsburgh coal bed stands today as probably the largest contributor of wealth of any single mineral deposit in the world. If it is not, what other deposit is? It has contributed to Pennsylvania alone more than 2,500,000,000 tons of high-grade coal worth nearly $4,000,000,000; since 1910, it has added more than $2,500,000,000 to the value of Pennsylvania's mineral output. In 1920, this bed2 contributed 127,227,000 tons of coal as follows: Pennsylvania, Pittsburgh district........................ 38,245,000 Connellsville district................................. 34,095,000 Weatmoreland-Ligonier district........................ 16,107,000 88,447,000 West Virginia, Fairmont district........................ 15,571,000 West Virginia-Ohio, Panhandle No. 8 district............. 21,128,000 Maryland-Potomac (Est. one-third of production)......... 2,081,000 38,780,000 Total........................................... 127,227,000

Jan 1, 1927

By J. L. Meijering

Oxidation hardening of cylindrical and spherical specimens first decreases with depth below the surface, but then increases again as the center is approached. This is in agreement with the view that this change in hardness is mainly determined by the change in velocity of the oxidation boundary, which affects the dispersion of the oxide. WHEN a thick slab of silver containing 0.3 pct Mg by weight is internally oxidized, the hardness measured on a cross section is found to decrease considerably with distance from the surface.&apos; This phenomenon has been attributed to the diminution of the velocity of the oxidation boundary. The smaller this velocity is, the more slowly the free-oxygen concentration rises towards the concentration in equilibrium with the oxygen gas. And a small 0 concentration favors dissociation and thus conglomeration of the oxide. For instance, the hardness decreases more rapidly during long annealings in nitrogen than in air.&apos; Measurements by Gregory and Smith3 on sections through internally oxidized Al-silver wire showed a smaller variation in hardness, probably because the wire diameter was only 0.9 mm. Wood4 found a drop in hardness with depth in internally oxidized Al-copper strip, and also—by electron microscopy—the concomitant increase in Al2O3 particle size. Under certain circumstances internal oxidation leads to formation of rather irregular inner oxide films in the midst of dispersed oxide. This special sort of conglomeration—discussed in Ref. 5—is also favored by greater depth below the surface.3,5 In this paper hardness measurements in large diameter cylindrical and spherical specimens are described. Here the oxidation velocity* goes through ness initially decreases with depth but increases again towards the center. Normally, the diffusion coefficient D1 of oxygen is very large compared to D2, that of the dissolved metal. If, furthermore, the atomic fraction c2 of the latter is much larger than the O-solubility cl- but c2D2 << c1D1- the velocities in question are easily calculated2 to be: for the cylinder and for the sphere. Here p is the radial coordinate of the oxidation boundary and R the specimen radius, which in dilute silver alloys is constant, as no external oxidation occurs. These equations have been derived for a divalent solute; for nondivalent solutes c2 has to be multiplied by half the valency. The equations are not valid near the center. For which can be considered as a standard case,2 the Eqs [I] and [2] begin to yield U-values which are appreciably too high for p/R = 0.05 and 0.15, respectively. But at the v-minima they are still very good approximations. These minima lie at p = emlR= 0.37R in the cylinder and p = 1/2 R in the sphere. Other factors besides the velocity v will also influence the hardness. The oxide concentration cox is constant in a flat strip, apart from a narrow region in the middle,2 but in cylindrical and spherical specimens cox decreases steadily with depth. When C1 << c2 and c1D1 >> c2D2 one can calculate

Jan 1, 1961

FRED TURRELL GREENE Fred Turrell Greene was born in Brooklyn, N. Y., Nov. 22, 1872. His father, William A. Greene, was born in Providence, R. I., and his mother, Angenora Semlear, was born in Brooklyn, N. Y. Fred&apos;s early school clays were spent in Boston, whence his father moved to Canada in 1882. Attending first the Collegiate Institute in Toronto, .then the High School at Berlin (now Kitchener), Ontario, where he graduated, Fred progressed to the Toronto University and the Michigan College of Mines, at Houghton, where lie graduated in 1897. He secured employment almost immediately at Butte with the engineering force of the Boston & Montana Consolidated Silver Mining Co., under Chas. S. Batterman. In 1899 he went to Rossland, B. C., where he spent more than a year as mining engineer and assistant superintendent of the War Eagle Consolidated Mining and Development Co. and the Center Star Mining Company Ltd. Returning to Butte in 1900, he acted as assistant geologist for the Anaconda Copper Mining Co. until 1906, when he filled a similar position in St. Paul with the Great Northern Railway for about two years. From 1908 until his tragic death on Christmas day, 1917, his headquarters were in Butte, where he enjoyed an excellent reputation -as consulting mining engineer, with a rapidly widening circle of clients. During the past four years he had been consulting engineer for the Elm Orlu and other mines controlled by Hon. W. A. Clark, and was in charge of underground developments and law-suit preparations for the celebrated apex case between the Elm Orlu and the Butte & Superior companies. At the time of his death he was in charge of similar work for the Utah Metals Co., in connection with their mines at Bingham, Utah. He was also for some years active in the Coeur d&apos;Alenes, as consulting geologist for the Federal and other companies there, and was considered an authority on this as well as the Butte district. Mr. Greene was unmarried, and is survived by his parents, a younger brother, who is in the army, and one sister, Mrs. James A. Hatch, of New York. Some of the most important and valuable ideas regarding the nature and origin of copper ores have originated in Butte, since that district is not only one of the greatest examples of mineralization known in any land, but has gone through a long course of mining litigation, and was, one of the first to be studied intensively by geologists. In connection with the early investigations, as well as with the most recent in that camp, Mr. Greene played an important part. His conscientious devotion to his duties and his intelligent handling of the problems presented for solution sufficiently explain the esteem in which he was held by his employers and his professional associates.

Jan 5, 1918

By Joseph M. Dawson

Although there was a very great increase in drilling activity along the fault line of south Texas during 1937 as compared with the previous three or four years, and although seven new fields were discovered, it cannot be said that any major development of importance took place. There were slightly over 550 completions during 1937, of which nearly 350 were oil wells as compared with some 275 the preceding year, of which 169 were oil wells. This increase in drilling activity was occasioned almost entirely by the greater interest in and development of Austin chalk production, principally in Caldwell, Guadalupe and Bastrop Counties. Seven fields were found, of which a brief description is given in Table 3. None has as yet assumed anything of major importance, and it is doubtful whether any will be classified as major discoveries through further development. Two were producing from the Edwards limestone, one from serpentine and the other four from the Austin chalk; the latter may be classified as extremely erratic in nature. The major discouraging feature of the year was the rise and subsequent fall of interest and importance of Austin chalk production. Many new operators came into this district to drill and produce Austin chalk oil toward the first of the year, but in the latter months the production decline from this formation was so rapid and the production so erratic that drilling operations fell off materially and interest largely abated. This was particularly true of the Branyon field in Caldwell County, and the same statement is applicable to the Pearsall field, Frio County. The latter field, covering some 5000 acres and owned and controlled entirely by the Amerada and Rycade, had early completions from the Austin chalk as high as 22,000 bbl. per day. The decline was extremely rapid and the maintained production from 17 wells is only around 700 bbl. per day after a total recovery of less than one-half million barrels. Present estimates of recoverable oil from Chalk vary from 2000 to 5000 bbl. per acre. A new process for the completion of producing wells from the Edwards limestone, particularly applicable to old producing areas, was developed, in that the penetration of the Edwards lime in drilled wells is now only 1 or 2 ft. as compared to between 15 and 75 ft. in wells drilled several years ago. Many new wells have been drilled in old Edwards lime producing

Jan 1, 1938

By L. C. Snider

All important industries have certain basic principles in common which govern them and give them a family resemblance. In addition, each industry has a certain individuality due to some principle or principles which govern, or are accepted as governing, that industry and which is not effective in others. The customs and practices of an industry depend on these basic principles much as the corollaries follow a proposition in geometry. After the proposition is proved or is accepted as proved, the corollaries are seen to be true almost without additional evidence or proof. In many cases, the corollaries are more important in practical affairs than the proposition on which they depend. By continued application the corollaries may come to be accepted as law and the fact that their truth depends on the correctness of the fundamental proposition is forgotten or ignored. If it is discovered that an error was made in demonstrating the proposition and that the proposition is untrue, the corollaries are, in most cases at least, equally untrue. Considerable time may be required, however, to realize the fact that the corollaries have failed, particularly if they have been embodied in custom and law. For example, in the business of government the proposition that women are intellectually inferior to men was formerly considered, by most men at least, to be duly proved if not axiomatic. This propositiot was never embodied in law, but its corollaries—that the rights of the wife in property and even in her own children were inferior to the rights of the husband, and that women had no place in governmental affairs—were duly incorporated in law or so completely approved by custom that they had the effect of law. Developments of the past few decades have proved, to the satisfaction of the majority, that woman&apos;s intellectual inferiority to man had not been satisfactorily demonstrated, and that the proposition that she was inferior, although accepted for many generations, was untrue. It was not so great a shock to men to discover that this proposition was wrong as it was to find out that its corollaries were also untrue and that the laws embodying them were not good laws and were subject to repeal. The adjustments which give women equal rights with men

Jan 1, 1932

By Douglas Bunting

The first presentation of this paper was before the Pennsylvania Anthracite Section of the Institute in May, 1914, after which a committee was selected to verify and add to the data contained in the original paper. The author is indebted to G. W. Engel, H. W. Montz, R. V. Norris, and H. H. Otto, of this committee, for additional information. I also wish to acknowledge the courtesies extended me by a number of the mining companies for information relative to accidents, systems of proving, and mining practice. The paper should bring forth additional criticism and recommendations, which will be of value in establishing future practice relative to this subject. Throughout the northern anthracite field of Pennsylvania glacial and alluvial deposits of sand, gravel, and clay exist in varying quantities. The extent and character of these deposits are described by N. H. Darton in Bulletin 45 of the U. S. Bureau of Mines, entitled, Sand Available for Filling Mine Workings in the Northern Anthracite Basin. It is estimated that the northern field contains 10,000,000,000 tons of these deposits, or a sufficient quantity to cover the 176 square miles of coal area to a depth of about 25 ft. These deposits of sand, etc., overlying the coal measures attain a maximum depth of more than 300 ft., and are usually saturated to such an extent as to render them semi-fluid. It is this condition of fluidity that limits the mining of coal seams cropping in or in close proximity to these deposits, and it is in the interest of safer and more efficient mining methods under these conditions that the study of this subject is here presented. The dangers incident to mining under deep deposits of sand have long been realized by operators in the northern anthracite field, and much has been done to prove the contour of the rock and vein croppings underlying these water-bearing deposits of sand and gravel. Although, as far as we know, the accidents of the past have not resulted in the loss of life, except in two instances, yet nearly all were attended with more or less miraculous escapes of men working in the vicinity of the breaks, so that the probable existence of pot holes, etc.,

Jan 1, 1915

By Y. C. Liu

THE existence of mechanical twins in bcc metals has long been known. With recent intensive interest in the mechanism of twin formation and its role in plasticity and crack initiation, a study of the general Characteristics of twin intersection appears pertinent. The scope of the present note will be limited to the crystallography of the twin intersections of (112) twins, without consideration of its mechanism, movement of atoms, crystal structure, or the strain energy involved at such an intersection. The twinning elements of (112) twins are considered to be K1 = {112}, n1 = (111) and K2 = {112}, n2 = (111) with a twin shear of 0.707. The crystallographic features of twin intersections have been worked out in detail by Cahn.1 The present work applies the general principles postulated by Cahn to the intersections of (112) twins. The basic conditions for the twin intersection are: 1) The trace of crossing (A) and the secondary (C) twins in the planes of the crossed twin (B) must be parallel. 2) The direction (n1) and magnitude (s) of shear must be identical in the crossing and secondary twins. Also the sense of shear must be the same. These two conditions have to be fulfilled in order to maintain geometrical continuity at the twin interfaces. Fig. 1 shows the perspective representation of how these two conditions are fulfilled at the intersection. This type of intersection will be named Type-I. It is the purpose of this note to point out the existence of another type of intersection, Type-II, as shown in Fig. 2. In this type of intersection, the crossing twin A remains straight and the crossed twin B has been bent. The two conditions laid down by Cahn must also be met. This leads to the following corollary conditions: 1) The interface between twins B and C must be parallel to the twin habit of crossing twin A. 2) n1c must be parallel to n1A. 3) The twin shear (s) of twin C must be exactly equal to and in the same sense as that of crossing twin A. Thus, in order for the Type-II intersection to take place, the twining elements of secondary twin C must fulfill the above three conditions with respect to crossing twin A. Let K1 of crossed twin B be (112). All indices of the matrix can therefore be converted into new in-

Jan 1, 1963

By M. M. Fidlar, Ralph E. Esarey

A marked decrease in drilling during 1937 in Indiana seemed to have no undesirable effect upon the oil and gas industry. Instead, production figures for oil showed a small increase over those for the preceding year, although not so much gas was marketed as in 1936. Drilling activity was centered in proven areas, and the proportion of dry holes to the number of wells drilled decreased somewhat. During 1937, including old wells drilled to deeper horizons, 134 wells were completed in Indiana, of which 39 were oil wells, 39 gas wells, and 56 dry holes. Nearly 75 per cent of the holes were drilled in proven areas. Of the 36 wells drilled in wildcat areas, only four found commercial production. Wildcat wells were especially numerous in Vigo, Pike, Perry and Spencer Counties. Exploratory drilling activity in Vigo County resulted in part from the drilling of the discovery well in the new Prairie Creek field. In Pike County, wildcat wells were drilled in the search for new supplies of gas to meet the demand in the southwestern portion of Indiana. Drilling in both proven and wildcat areas in Perry and Spencer Counties continued to be heavy, because of the presence of shallow Missis-sippian sands and the resulting low cost of drilling and equipping. At the end of the year, 42 of the wells started in 1937 were not completed. Only a few locations were drilled in the old Trenton field, but the wells, many of them 40 years old, continued to furnish a small supply of gas for domestic consumption. Oil production in the Jay County portion of the Trenton area was nearly twice that of 1936, owing in part to a vacuum system installed on several leases. The Harrison County (Laconia) gas field is being developed northward to offset water encroaching from the south. This water in the black shale threatens to put an end to the steady production that this field has furnished for many years. During 1937, the Oaktown gas field again furnished more gas than any other field, but production in that area showed a marked decrease over the marketed gas for 1936. During the early months of the year, seven wells were completed in the Oaktown field to bring the total number of producing wells to over 40. At present, all the operators in the area are

Jan 1, 1938

By Jorge Munoz Reyes

There are three main oil areas in Bolivia (Fig. 1) although so far only one has yielded petroleum in commercial quantities. The Sub-Andean zone is along the easternmost ranges of the Andes, bordering the large eastern and northeastern lowlands. It extends from the Peruvian frontier, north of Lake Titicaca in a southeasterly direction towards the city of Santa Cruz and from there southward to the Argentine border. This zone forms a belt about 1200 km. long by 100 km. wide, and comprises a series of parallel, very rugged, low ranges. Oil has been known and utilized by the natives in these regions since colonial times, from the large number of seepages, which in modern times have led to the discovery of many fields. The second oil zone of Bolivia lies along the eastern and southern borders of Lake Titicaca, on the Andean high plateau, at an average altitude of 13,000 ft. above sea level. It comprises an area of approximately one million hectares (2,470,000 acres). Several seepages are known here, but little development has taken place, because of the difficulties encountered, as the greater part of the territory is covered by volcanic tuffs and ashes, which conceal the structure underneath. The third area is called the "Central zone," and is in the heart of the country, in the Department of Cochabamba, covering approximately five million hectares (12,350,000 acres). This area consists mainly of broad valleys flanked by low rolling ranges. Natural seepages are not known to exist, but there are secondary evidences of the presence of oil. The outcropping rocks are mainly Paleozoic (Silurian and Devonian sandstones and shales). Albertite and other forms of polymerized petroleum have been found in this region. Of these three main oil areas, only the first one is at present productive on a small commercial scale. This zone, developed almost exclusively by the Standard Oil Co. of Bolivia, a subsidiary of the Standard Oil Co. of New Jersey, is divided from south to north into the following local fields: 1. Bermejo (On the Argentine border) 3. Sanandita 5. Camatindi 2. San Telmo 4. Caigua 6. Machareti

Jan 1, 1935

By O. C. Wheeler

The production of oil in Colombia during 1933 was at the lowest level since the completion of the loop of the Andian pipe line in 1927. The commercial production amounted to 13,157,641 bbl., all of which was produced from the Infantas and La Cira structures of the Tropical Oil Company. One of the most important developments was the discovery of what may be commercial production on the Colombian Petroleum (Gulf) Company&apos;s Tarra anticline on the Barco Concession in eastern Colombia near the Venezuelan border. This promises to become the second commercially productive area developed in Colombia and, perhaps, one of major importance. Applications made in 1931 for concessions under the new Colombian petroleum law were ratified covering the Putana application of the Tropical Oil Co. and others of local Colombian and French interests west of the Carare River. On none of these concessions has any development work yet been initiated. South American Gulf Oil Company The following information covering the activities of the South American Gulf Oil Co. was furnished by E. S. Bleecker, chief geologist of the company. Magdalena Valley.—No development work was undertaken during the year either on the Valenzuela property acquired from the Colombian Syndicate or on the lands obtained from the Leonard Oil Development Co. near the Sogamoso River. The Valenzuela property was relinquished and a portion of the material was removed therefrom to the Leonard property near by. Colombian Petroleum Co.—The Colombian Petroleum Co., controlled by the Gulf interests, pursued an active development campaign on the Chaux-Folsom or so-called Barco Concession in the Department of North Santander. The drilling of the first well was begun early in the year on the north Petrolea dome of the Tarra anticline and at 490 ft. a heavy flow of oil, gas and salt water was encountered. On blowing in unexpectedly, the well caught fire, and after being extinguished was controlled only by pumping large quantities of cement into the formation and plugging the well. The drilling of the second test, No. 1-A, approximately one kilo-

Jan 1, 1934