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By AIME AIME

IN many countries the lack of liquid petroleum supplies has centered interest upon the hydrogenation of coal and coal tars for the preparation of motor fuel. In the United States, hydrogenation has been of greater interest for grading up low-value petroleum fractions to the more valuable volatile fuels and for the preparation of a variety of premium products, including aviation gasolines, solvents, Diesel fuels, and lubricating oils. Chemically, the basic reason for this process is that, as shown in Table 1, the ratio of hydrogen to carbon (H/C ratio) in available raw materials is quite different from that characterizing the products sought.

Jan 1, 1936

By E. H. Citron

CLEANING fine coal in jigs is not new in Europe, where the feldspar jig is being used almost exclusively for this purpose. A feldspar jig operates with an artificial bed made up generally of feldspar or other hard rock material. Dimensions and specific gravity of this material must be of suitable values for good bedding qualities. For good efficiency, the size should range between 1x2 in. and 2x2x½ in. thick. The disadvantage of an artificial bed is that it is not mobile and must be replaced every so often with new material to obtain good cleavage characteristics. A semi-mobile bed has been developed to retain only a part of the feldspar on the sieve screen— the other part is drawn off with the refuse material, from which it is reclaimed and returned to the jig feed. Recirculating this feldspar rock offers definite advantages. However, in time it will lose its original shape because of wear, and new bed material must be added to the jig feed. The latest feldspar jigs arc generally air-pulsated, Baum-type jigs, although more than 70 pct of the feldspar jigs operating in Continental Europe are still of the piston type. These jigs are very popular in Europe, but they do require a great deal of time and attention. New Theory to Eliminate Artificial Bedding: At the preparation plants of Pittsburg & Midway Coal Mining Co. it has always been the contention that a small piston-type jig could be developed to clean fine 1/4x0-in. coal down to 28 to 60 mesh efficiently by obtaining and admitting bedding material from the present plant refuse circuit to the jig feed. This eliminates use of artificial bedding materials. The jig should incorporate these essential adjustable features as follows: Adjustable Sieve Screen A screen that can be raised and lowered to increase or decrease washing compartment depth. The sieve screen also can be set on an incline level, or decline. Adjustable Plunger Eccentric Length of stroke can be adjusted to increase or decrease pulsion and suction. Variable Plunger Speed Variable speed reducer for decreasing and increasing the number of strokes per minute. Water Distribution Adjustable baffle plate separating the plunger and sieve compartment so the water can be distributed uniformly over the entire sieve screen area. Refuse Ejector Special unique rubber-type refuse ejector gate operated by air and electrically controlled (as a conventional jig). Automatic Control Conventional float that measures the specific gravity of the coal-water refuse medium in the jig is of the submerged type. The float is mounted on a vertical stem held in position by two parallel arms. A movable weight regulates the effective specific gravity of the float. The float stem can be raised and lowered, having a graduated scale to indicate the depth of bed for the setting of the float. Hutch Drawoff Hutch material is drawn from the cell compartment to the elevator compartment by gravity. The first one-cell experimental jig incorporating all these features was built in January 1955 by Ore

Jan 1, 1959

By Donald Barton

THE theory of gravitation is based on Newton's law that any two bodies exert a mutual attraction which is proportional to the product of their masses and inversely proportional to the square of the distance between them; i. e., A =KRM/R2 (1) where K is a constant, M and m are the respective masses of the two bodies, and R the distance between them. In the earth's gravitational system, the earth is one of the bodies; the other may be any body within or without the earth. In theoretical dis¬cussions and calculations in regard to gravity, that other body usually is taken as a unit of mass: in the C. G. S. system, a body of one gram in mass. GRAVITY AND LEVEL SURFACES Gravity is defined in geophysics as the force of attraction exerted by the earth, towards itself, on a body of unit mass. The intensity of gravity is usually expressed in dynes of force or in centimeters of acceleration. In geophysical work in America, most commonly it is expressed in dynes (per gram) with the "per gram" understood and not directly expressed. In geophysical work in Europe, most commonly it is expressed in centimeters per second per second (cm./sec.2) and less commonly merely as centimeter-gram-second units (C. G. S.). At sea level, the intensity of gravity amounts very nearly to 980 dynes. The vertical is the direction along which the attraction of gravity is exerted at any point. . In most cases, it is very nearly, but not quite, per¬pendicular to the earth's surface. The path that would be taken by a body falling freely through space toward the earth is vertical at each point and may be spoken of also as "the vertical," or as the line of the vertical, or as a line of force of gravity. At the earth's surface it com¬monly is very nearly, but not quite, a straight line.

Jan 1, 1928

By I. J. Hegyi, J. J. Tietjen, H. Nelson, J. I. Pankove

The fabrication of p-n junctions in GaAsl-,P, alloys by a vapor-phase gowth technique has for the first tirne resulted in room-temperature injection lasers capable of operating over a broad range of wavelengths extending into the visible region of the spectrum. The shortest wavelength achieved to date is 6750A at room tetnperature. In addition, at 78°K the threshold current density values for these lasers are generally the lo~vest reported, and the emitted radiation extends to the lozc,est wavelength ever attained (6350A). With lasers fabricated from material containing 14 pct Gap, quanticm efficiencies of 26 pct and peak power outputs of 25 zu were obtained at room temperature. ALTHOUGH room-temperature operation of GaAs injection lasers has been well-documented,&apos;-5 the operation of GaAsl-,P, (x > 0) laser diodes has been restricted to relatively low temperatures.8-&apos;0 This has been previously attributed5, 7, 10-12 partially to the difficulty of preparing single-crystalline GaAsl-& alloys having a high degree of chemical homogeneity and purity. Also, with these materials it has been difficult to prepare high-quality, abrupt p-12 junctions by diffusion techniques; and, in turn, this has made it difficult to obtain optimum electrical properties for room-temperature operationL3 in the resulting laser diodes. As a result, GaAsl-,P, laser diodes have not been efficient enough to permit operation at room temperature. For example, using diffused structures, only a few diodes were obtained which could be operated even close to room temperature (255K)." Recently, a vapor-phase growth method of preparing epitaxial deposits of GaAsl - .P, alloys has been described,14 and the high-purity and homogeneity of these materials has been previously demonstrated. Of special significance, with this technique, n- or p -type doping can be initiated or discontinued at any time and at almost any rate during the crystal growth so that the donor and the acceptor concentrations can be easily controlled to obtain desired impurity profiles. This permits high-quality, abrupt p-TZ junctions to be vapor-phase grown entirely during the crystal growth process, so that diffusion or other p-n junction fabrication processes are unnecessary. After growth, the device does not have to be heated to elevated temperatures, which avoids the possible unwanted introduction and motion of both impurities and lattice defects. Using the vapor-phase growth method cited above, over 300 room-temperature injection lasers have been prepared from GaAsl-,P, alloys having compositions in the range of 0 5 x 5 0.41. These lasers have emitted cohe~ent radiation in the spectral range of 8350 to 6350A at 78°K or from 9000 to 6750A at room temperature. The threshold current densities of the best lasers are independent of the alloy composition over the range 0 < x < 0.2 and compare favorably with values for good GaAs lasers.&apos; MATERIAL PREPARATION Multilayer, epitaxial deposits of GaAsl-,P, alloys are prepared by a vapor-growth technique described elsewhere.14 With this technique, the individual layers which comprise the multilayer structure are prepared sequentially in the deposition apparatus without interrupting the crystal growth. The epitaxial layers are deposited on GaAs substrate surfaces oriented normal to the ( 100) direction. The substrate wafers employed in this study were usually doped with tellurium to an electron concentration of approximately 2 x 10" per cu cm. To avoid strains, the first 10 to 15 p of the deposited material is uniformly graded from pure GaAs to the specific GaAsl- ,P, alloy composition of interest. The GaAsl - ,P, alloy growth is then continued to form a layer of constant composition having a thickness in the range of 25 to 75 p. Both the graded region and the layer of constant composition are doped with selenium to an electron concentration of about 2 x 10" per cu cm. The p region of the diode is then incorporated in the crystal by abruptly changing the dopant concentrations in the vapor phase to facilitate doping with zinc. This layer has a hole concentration of approximately 3 X 1019 per cu cm and typically is 50 p thick. DEVICE FABRICATION In general, the GaAs substrate and the region of graded composition are removed. Ohmic contacts are made to the n-type side by tin evaporation and to the p-type side by an electrodeless nickel deposition. This is followed by an electrodeless deposition of gold on both sides. The crystal wafer is then cleaved along (110) planes and sawed into rectangular parallelepipeds. Typical dimensions are 100 by 300 for the junction area and 100 µ for the diode height. The diodes are either soldered to a copper stud or pressure-mounted in a copper clip. RESULTS AND DISCUSSION Approximately 400 laser diodes having compositions in the range of 0.41 have been prepared by the method described above. Each laser was routinely tested at liquid-nitrogen temperature. The lasers were operated with l-psec current pulses at a repetition rate of 60 pulses per sec. The parameters of greatest practical interest are the photon energy or wavelength of the laser output and the threshold current density. Fig. 1 shows the variation of photon energy with alloy composition at 78°K. The composition was determined from the lattice constant of the material obtained by X-ray back-reflection measurements. Although there

Jan 1, 1968

By Arthur S. Dwight

From the latest and best literature on lead-smelting, little can be learned concerning the present state of the art of mechanical feeding in the United States. H. O. Hofman, in his Metallurgy of Lead (5th ed., 1899), briefly describes the main features of the system in use at Pueblo, Colo., and later (p. 235) says " the only successful mechanical feeding, as far as the writer is aware, is that found at the works of the Pueblo Smelting and Refining Co." H. F. Collins, in his Metallurgy of Lead and Silver (London, 1899), covers American practice pretty thoroughly; but as to mechanical charging, he says: "The German plan of taking off the gases by means of a small iron pipe suspended in the center, and the plan of charging by means of cup and cone, as in iron blast-furnaces, have both been tried, but have not found favor, chiefly on account of the difficulty of obtaining free access to the furnace-shaft for barring, etc., with such devices."&apos; . H. W. Hixon, in his Notes on Lead and Copper Smelting (3d ed., New York, 1900), gives a description and drawing of the Hixon feeding device, as originally installed at East Helena. Evidence that this system of feeding has passed its experimental stage, and deserves more serious consideration than it has heretofore received, is furnished by two large plants—the Pueblo and the East Helena—of the American Smelting and Refining Co., where mechanical feeding has been in continuous and successful operation for a considerable period; one new plant now erecting at Salt Lake City, Utah, and one old one belonging to the same company, the El Paso works, now being rebuilt after a disastrous fire, in both of which mechanical feeding is to be a prominent feature ; one new plant of an independent concern at Torreon, Mexico, which will adopt mechanical feeding; and a number of other smaller plants, among

Jan 1, 1902

By H. J. Ramey, I. S. Bousaid

Experimental results on the oxidation reaction kinetics in the forward combustion oil recovery process are presented. A total of 48 runs were made wherein a stationary thin layer of coked, unconsoli-dated sand was burned isothermally in a combustion cell. Individual runs were made at various temperature levels to permit determination of the effect of temperature upon the reaction. An expression was obtained for the burning rate of carbon as a function of carbon concentration, combustion temperature and oxygen partial pressure. The carbon burning rate for two types of crude oil indicated a first order reaction with respect to both carbon concentration and oxygen partial pressure. The effect of combustion temperature on the reaction rate constant matched the Arrhenius equation. The activation energy was similar for the two crude oils examined. The activation energy decreased for a porous media containing clay. The rate of oxidation of crude oil at reservoir temperature was found to be significant. Other significant findings included information on hydrogen-carbon content of fuel residues, fuel reactivity and the products of combustion. INTRODUCTION The production of crude oil by underground combustion has been studied in the laboratory by many investigators.1-5 Results of laboratory and field experiments have been reported in the literature describing the forward combustion process. But as yet, no qualitative or quantitative study of the kinetics of fuel combustion involved in this process has been reported. The fuel concentration and the rate at which fuel is burned at the front are important factors governing the air requirement in a forward combustion operation. Although the fuel is essentially unrecoverable crude, the air required to burn the fuel is an important economic factor in this process. Because fuel is burned, the heat transport associated with forward combustion is a key and unique feature of this new oil recovery method. Many investiga-tors5-9 have presented information on the heat transmission and fluid mechanics involved in forward combustion. Berry and Parrish10 demonstrated the utility of considering reaction kinetics in reverse burning. From differential thermal analysis, Tadema11 presented a qualitative discussion of the nature of reactions between oil and oxygen in combustion oil recovery. Although little quantitative work has been done on the reaction kinetics involved in forward combustion oil recovery, an extensive literature does exist on combustion of carbons and oils, and carbonaceous residues from cracking catalyst pellets. Dart, et al., 12 studied the combustion rate for oxidation of carbonaceous residues on clay catalyst pellets, and found the reaction to be second-order with respect to carbon concentration, and first-order with respect to oxygen partial pressure for carbon concentrations less than 2 weight percent of the catalyst weight. The reaction appeared to be first-order with respect to carbon concentration for concentrations greater than 2 percent. Metcalfe13 noted that other workers had found that aging of the fuel during the combustion process was responsible for changing coke properties, and it accounted for the apparent second-order carbon concentration effect found by Dart, et al. It appears that burning of residues from cracking pellets is first-order with respect to both carbon concentration and oxygen partial pressure. Dart, et al., also observed that hydrogen in the hydrocarbon residue appeared to react faster than the carbon. Lewis, et al.,14 studied oxidation of charcoal, coke and graphite in a fluidized bed. Gas velocities were high enough to partially lift and circulate the carbon particles. Their results indicated first-order reaction dependency with respect to both carbon concentration and oxygen partial pressure. One

Jan 1, 1969

By Dunbar D. Scott

The development in the perfection of mine-surveying instruments has been by no means rapid, as it has depended somewhat on the details of construction borrowed from astronomical and geodetic theodolites, largely on the restrictions laid down by mining companies and the prejudices of mine managers themselves, but more than all on the methods used in conducting surveys and the importance attached thereto. Mine-surveying, in some form or other, has been practiced from the very earliest times; but it has never kept pace with the other branches of surveying, or even with the art of mining itself, and cannot be recognized as an exact science until shortly before the beginning of this century. The works of Hero of Alexandria, who lived in the second century B.C., are still extant, and contain descriptions of a rectangular sighting-instrument, which he invented and called a diopter. His improvement upon this simple construction, which possibly he devised for use in the Greek mines for rough leveling-purposes and for laying out any angle, must be considered, says Hübner," as the origin of the highly perfected theodolite of to-day. Whether this instrument came into general use during the first centuries of the Christian era, is not recorded; in fact, no writer undertakes to tell how mine-surveying was conducted until 1556, in which year Agricola expounds the principles of mining and metallurgy in his De Re Metallica, devoting the entire fifth chapter to the practice of mine-surveying (see Fig. 1). In mediæval times those who possessed any knowledge of engineering skill made strenuous effort to keep their art a secret, partly on account of the miners&apos; proverbial conservatism and partly for their own personal aggrandizement, and were, in

Jan 1, 1899

By H. E. Wheeler

The work described was carried out during 1917 and 1918 at the testing laboratory of Watertown Arsenal at the instigation of the Nitrate Division and later with the concurrence of the Cannon Section of the Ordnance Department, U. 8. A. The experiments follow three principal lines of work: First, the effect of nitrogen under pressure on steel containers of various compositions at a red heat; second, the effect of decomposing ammonia on various alloy steels, iron, and non-ferrous alloys; third, a new theory of the erosion of guns in respect to the effect of nitrogen in steel. Part I In the Haber process for the manufacture of ammonia from its elcnlents, it is necessary to have nitrogen and hydrogen of 1500 lb. per sq. in. (105.5 kg. per sq. cm.) at a temperature of 500 to 600&apos; C. The steel containers for these gases gave trouble by failing without apparent cause. When the General Chemical Co. began to develop its method for the production of ammonia, it experienced the same difficulty and, knowing that the Haber process had solved the difficulty by the use of alloy steels, it made several small steel bottles of different compositions and kept them filled with these gases at this pressure and temperature until they failed. The time of service varied from a few days, for the plain steel casting, to two years for a chrome-vanadium forging. Four of these steel bottles were sent to this laboratory for investigation; they were a plain carbon-steel forging, a nickel-stee1 forging, a chrome-vanadium steel forging, and a chrome-steel forging. The time of service was as follows: plain carbon steel, 4 mo.; nickel steel, 6 mo.; chrome-vanadium steel, over 2 yr.; chrome steel, 4 mo. When these containers were cut open and the cross-section surface polished, they showed an inside zone with a different luster from the rest of the metal. Upon etching, this zone was almost unaffected while the rest of the steel etched normally.

Jan 1, 1922

By H. E. Wheeler

The work described was carried out during 1917 and 1918 at the testing laboratory of Watertown Arsenal at the instigation of the Nitrate Division and later with the concurrence of the Cannon Section of the Ordnance Department, U. 8. A. The experiments follow three principal lines of work: First, the effect of nitrogen under pressure on steel containers of various compositions at a red heat; second, the effect of decomposing ammonia on various alloy steels, iron, and non-ferrous alloys; third, a new theory of the erosion of guns in respect to the effect of nitrogen in steel. Part I In the Haber process for the manufacture of ammonia from its elcnlents, it is necessary to have nitrogen and hydrogen of 1500 lb. per sq. in. (105.5 kg. per sq. cm.) at a temperature of 500 to 600&apos; C. The steel containers for these gases gave trouble by failing without apparent cause. When the General Chemical Co. began to develop its method for the production of ammonia, it experienced the same difficulty and, knowing that the Haber process had solved the difficulty by the use of alloy steels, it made several small steel bottles of different compositions and kept them filled with these gases at this pressure and temperature until they failed. The time of service varied from a few days, for the plain steel casting, to two years for a chrome-vanadium forging. Four of these steel bottles were sent to this laboratory for investigation; they were a plain carbon-steel forging, a nickel-stee1 forging, a chrome-vanadium steel forging, and a chrome-steel forging. The time of service was as follows: plain carbon steel, 4 mo.; nickel steel, 6 mo.; chrome-vanadium steel, over 2 yr.; chrome steel, 4 mo. When these containers were cut open and the cross-section surface polished, they showed an inside zone with a different luster from the rest of the metal. Upon etching, this zone was almost unaffected while the rest of the steel etched normally.

Jan 1, 1922

Alexander Forsyth, Southport, Me. (communication to the Secretary): In Mr. Irving&apos;s able and interesting paper he describes minutely the appearance of the wolframite and its association with the refractory siliceous gold-ore. He also describes this gold-ore, but fails to mention the important pockets of metallic gold found in the Lead City occurrence of it. I use the term " metallic " in preference to the more usual " free," for it has been found that this gold is not easily amalgamated. Metallic gold is comparatively rare in the refractory siliceous gold-ores of the Black Hills; hence its occurrence in considerable amounts in the Lead City wolframite district deserves notice. I possess a beautiful specimen from the Harrison mine. It is a lump of drusy, granular ore, about 6 in. in diameter. The gold .is " shot" through it in large and small pin-heads; and in two specially oxidized areas, each about 11/2 in. in diameter, it is peppered full. The famous " Grantz strike," made in the Lead City wolframite locality, produced many beautiful gold specimens. This district affords an excellent example of the repeated discovery of new mineral values upon old ground. By reason of its proximity to the Homestake vein, this wolframite deposit was inevitably traversed many times by experienced geologists, mineralogists and mining engineers, who evidently must have thrown aside, with no thought of wolframite, the lumps of " black iron " lying about. I have the admission of an able geologist that, six months before the wolframite was discovered, he visited some of the very mines where it occurred, and passed it by as magnetic iron-ore. At the time of the discovery, the mineral was scattered over the gold-mine dumps in no small quantities, having been culled as worthless out of the gold-ore. It remained for

Jan 1, 1902

By Gerald C. Dohm

INTRODUCTION After a mining company has discovered a mineral deposit, the problem is then how to mine and process that deposit the best way. The principal problem facing managers or engineers who must decide on mine plant size, equipment selection, and long-range scheduling is how one can optimize a property not only in terms of efficiency but also as to project duration. Mine opti¬mization is dependent upon the interaction of con¬tributing parameters which leads to maximizing the net present value (NPV) Realistic mine planning is the key, to the analysis. The process is to be used when evaluating undeveloped properties or when a complete revamping of existing facilities is scheduled The proc¬ess is not intended for detailed mine design but rather for property evaluation and feasibility studies. The derivation of the various input parameters will only be discussed to the point where a meaningful correlation can be made with the overall analysis. The interrelationship of the parameters will be the central point because most company guidelines and financial analysts have their own standards when deriving the various inputs. Assume that the data is totally acceptable and pro¬vides at least the following categories of information and guidelines- (1) mineral and waste inventory; (2) geologic, hydrologic, and geotechnical criteria; (3) topographic layout including property boundaries; (4) metallurgical flowsheet, recovery and design criteria; (5) access, water, power, and environmental base-line study; and (6) financial constraints (minimum rate of return, payback period, etc).

Jan 1, 1979

By Ian Wark

IN an earlier paper1 measurements of contact angles due to the effect of xanthates on mineral surfaces were reported. The solutions in which these measurements were made differed widely from those of modern flotation circuits. It is intended, however, by introducing, one at a time, the other principal reagents of flotation, to approach gradually the solu-tion composition of flotation liquors. The work now described is an attempt to determine the effect of one of the most important of these reagents-namely, sodium cyanide-on the establishment of air-mineral contact. The work has been carried out for the following companies: Broken Hill South, North Broken Hill, Zinc Corporation, Electro-lytic Zinc of Australasia, Mount Lyell Mining and Railway, and Burma Corporation. Since the effect of cyanide is inseparably connected with the alkalinity, the results cited below deal with the mutual effects of alkalis and cyanide. Alkalis alone exert a significant effect on the air-mineral contact but comparatively large amounts are required. Since the addition of a small amount of cyanide greatly decreases the degree of alkalinity necessary for the suppression of contact at surfaces of any of the minerals experimented with (except galena) and since alkalis are rarely used alone in practice, little attention has been paid to cyanide-free solutions. It was shown in the previous paper that, excluding the dixanthogen effect, whenever contact was practicable at all in an ethyl xanthate solution the angle of contact was 60°. There is, therefore, less necessity to measure equilibrium contact angles; in fact, the experiments herein described have generally been conducted with a view to determining whether contact is possible and not to measuring the actual value of the contact angle. The separations which have generally to be effected in dealing with complex sulfide ores are: (1) galena from sphalerite, pyrite, etc.; (2) sphalerite from pyrite and/or gangue minerals; (3) copper minerals from pyrite and gangue minerals; (4) pyrite from gangue minerals; (5) chal-

Jan 1, 1933

By Oliver Bowles

AMONG mining men as well as in the popular mind the conviction has held sway that mining is pre-eminently a western industry. True it is that gold, silver, copper and other metals have made the States of California, Colorado, Montana, Utah. Nevada and Arizona famous. The prominence attained by these States as mineral producers is, however, not measured alone by the money value of the products of their mines. While the metals are without doubt indispensable in industry, the glamour of the precious metals, and the lure of copper, lead and zinc have given to their ore deposits a sentimental interest that often quite out-weighs their commercial importance. Today a great group of more commonplace minerals are finding a place in commerce and industry rivaling that of the metals, but there is little sentiment attached to them, and,. therefore, they attain relatively little publicity. This is the great group of the non-metallic minerals, exclusive of fuels and oils, including stone, sand and gravel, cement, lime, gypsum, asbestos, mica, phos-phate rock and many others. Almost unnoticed they have grown in production to almost unbelievable pro-portions. The estimated value of metal production for 1925 is given as $1,380,000,000, of the non-metals (ex-cluding fuels) $1,294,000,000. The non-metallic industries are not new, many of them date back almost to pre-historic times; but, as the greatest of them (on a tonnage basis) provides raw materials for the construction industries, it required the activities of the present age of construction to bring about their enormous development. Many of them enter manufacturing as well as con-struction. Non-metallic minerals constitute the back-bone of our great chemical industries. While construction and manufacture reach to all parts of the country their widest development has been in the great industrial centers of the eastern Seaboard and the middle West. Consequently the raw materials of mineral origin required for these great industries have attained a remarkable growth in the eastern half of the- United States. In compiling figures of mineral production for 1924, for which more complete data are available than for later years, the surprising fact is brought to light that the non-metallic mineral produc-tion alone of some of the eastern and middle-western States exceeds by a substantial margin the total min-eral production of some of the western States that have been classed as essentially mining States. Thus the non-metallic mineral production, exclusive of coal and petroleum, of the State of Ohio, was approximately $150,000,000; of Pennsylvania $175,000,000; and of New York $107,000,000. For the same year, 1924, the total mineral production of Utah was $84,357,000; of Montana $70,632,000; of Colorado $61,488,000; and of Nevada only $26,226,000. Even Minnesota, with its enormous iron ore production, reached only $107,845,-000, or a sum about equivalent to the non-metallic min-eral production of the State of New York.

Jan 8, 1927

By Raymond D. Sloan

Retaining third place in crude-oil production among the nation&apos;s oil-producing states, Oklahoma&apos;s output in 1942 totaled 137,792,000 bbl., a decline of 9.4 per cent from the previous year&apos;s total of 152,117,000 bbl. Production declined from an average of 403,000 bbl. daily in January 1942 to an average of 355,000 bbl. during December, a reduction of 48,000 bbl. daily (11.9 per cent) during the year. At the end of 1942 it would appear inevitable that the downward trend in production will continue in 1953 unless halted in the immediate future by greater than normal discoveries and development. To Jan. I, 1943, Oklahoma has produced 5,067,013,000 bbl. oil crude oil. Development and Exploration Development dropped abruptly in 1942, reflecting the lack of any sizable discoveries and the effect of the provisions of Federal Well Spacing Order M-68, which became effective in December 1941. In all, 1210 wells were drilled in 1942. This represents a decrease of 42.7 per cent from the 1941 total of 2110. Of the total wells completed, 553 (45.7 per cent) were oil wells with an average initial production of 443 bbl.; 102 (8.4 per cent) were gas wells with an average initial of 3,359,000 cu. ft.; and 555 (45.9 per cent) were dry. Although the number of completions declined sharply, the total of 320 wildcats completed (26.4 per cent of all wells) repre-sents a decrease of only 2.7 per cent from the previous year&apos;s figure of 329. Of the wildcats drilled, 44 (13.8 per cent) were oil wells, 13 (4.0 per cent) were gas wells, and 263 (82.2 per cent) were recorded as failures. Reconditioning of wells throughout the state resulted in a total recompletion of 355 wells. Of these, 234 were oil wells with a combined initial production of 96,808 bbl., 32 were gas wells with a total initial of 381,488,000 cu. ft., and 89 were abandoned. None of the 26 pools found in 1942 has developed into a major discovery. The Pauls Valley pool, Garvin County, is the most outstanding. Since its discovery in April, 14 wells with an average initial of 1898 bbl. have produced 803,000 bbl. of 42&apos; gravity oil from the Bromide zone. Development in this pool is believed to be almost completed. Other of the more important discoveries are the East Watchorn pool, Pawnee County; Guthrie Townsite and West Navina, Logan County; Brooksville and Macomb, Pottawatomie County, and the Liberty and Northeast Lucien discoveries in Noble county. The East Watchorn pool, at the close of the year, had 14 completed oil wells with an average initial of 989 bbl. from the Wilcox sand at 3930 it.; Guthrie Townsite, one well with an initial of 840 bbl. from dolomite at 5600 It.; West Navina, six wells with an average initial of 284 bbl. in the Lay ton sand at 5050 ft., Brooksville, eight wells in the Hunton at 4800 ft. with an average initial 01 355 bbl.; Macomb, one well with an initial of 160 bbl. in the IIunton at 4700 ft.; the Liberty pool, one well with an initial of 1268 bbl. in the second Wilcox at 4500 ft., and two wells in the Tonkawa sand at 2500 ft., with an average initial of 230 bbl. In the Northeast Lucien pool, four wells were completed in the Wilcox at 5380 ft. for an average initial of 1164 bbl., and one well was completed in the Viola lime at 5255 ft. for an initial of 55 barrels.

Jan 1, 1943

By Raymond D. Sloan

Retaining third place in crude-oil production among the nation&apos;s oil-producing states, Oklahoma&apos;s output in 1942 totaled 137,792,000 bbl., a decline of 9.4 per cent from the previous year&apos;s total of 152,117,000 bbl. Production declined from an average of 403,000 bbl. daily in January 1942 to an average of 355,000 bbl. during December, a reduction of 48,000 bbl. daily (11.9 per cent) during the year. At the end of 1942 it would appear inevitable that the downward trend in production will continue in 1953 unless halted in the immediate future by greater than normal discoveries and development. To Jan. I, 1943, Oklahoma has produced 5,067,013,000 bbl. oil crude oil. Development and Exploration Development dropped abruptly in 1942, reflecting the lack of any sizable discoveries and the effect of the provisions of Federal Well Spacing Order M-68, which became effective in December 1941. In all, 1210 wells were drilled in 1942. This represents a decrease of 42.7 per cent from the 1941 total of 2110. Of the total wells completed, 553 (45.7 per cent) were oil wells with an average initial production of 443 bbl.; 102 (8.4 per cent) were gas wells with an average initial of 3,359,000 cu. ft.; and 555 (45.9 per cent) were dry. Although the number of completions declined sharply, the total of 320 wildcats completed (26.4 per cent of all wells) repre-sents a decrease of only 2.7 per cent from the previous year&apos;s figure of 329. Of the wildcats drilled, 44 (13.8 per cent) were oil wells, 13 (4.0 per cent) were gas wells, and 263 (82.2 per cent) were recorded as failures. Reconditioning of wells throughout the state resulted in a total recompletion of 355 wells. Of these, 234 were oil wells with a combined initial production of 96,808 bbl., 32 were gas wells with a total initial of 381,488,000 cu. ft., and 89 were abandoned. None of the 26 pools found in 1942 has developed into a major discovery. The Pauls Valley pool, Garvin County, is the most outstanding. Since its discovery in April, 14 wells with an average initial of 1898 bbl. have produced 803,000 bbl. of 42&apos; gravity oil from the Bromide zone. Development in this pool is believed to be almost completed. Other of the more important discoveries are the East Watchorn pool, Pawnee County; Guthrie Townsite and West Navina, Logan County; Brooksville and Macomb, Pottawatomie County, and the Liberty and Northeast Lucien discoveries in Noble county. The East Watchorn pool, at the close of the year, had 14 completed oil wells with an average initial of 989 bbl. from the Wilcox sand at 3930 it.; Guthrie Townsite, one well with an initial of 840 bbl. from dolomite at 5600 It.; West Navina, six wells with an average initial of 284 bbl. in the Lay ton sand at 5050 ft., Brooksville, eight wells in the Hunton at 4800 ft. with an average initial 01 355 bbl.; Macomb, one well with an initial of 160 bbl. in the IIunton at 4700 ft.; the Liberty pool, one well with an initial of 1268 bbl. in the second Wilcox at 4500 ft., and two wells in the Tonkawa sand at 2500 ft., with an average initial of 230 bbl. In the Northeast Lucien pool, four wells were completed in the Wilcox at 5380 ft. for an average initial of 1164 bbl., and one well was completed in the Viola lime at 5255 ft. for an initial of 55 barrels.

Jan 1, 1943

By H. E. Cook

The Ising model for the internal energy of a binary alloy has been used to obtain a general equation for the critical resolved shear stress of partially ordered crystals. The equation expresses the stress in terms of the Warren "alphas " and can be used to estimate the variation in strength with order without the assumption, present in the original formulation of this problem in terms of domain size, that order is complete within each domain and that the domains are of ungorm size and shape. In addition, it is the general equation, according to the Ising model, for strengthening by short-range order. Two applications of the equation are considered: One is an estimate of the variation in strength of CkAu with long-range order. The other is an estimate of the variation in strength of FeCo with quench temperature. Reasonable agreement is found with the variations reported in the literature. When the internal energy of an alloy crystal depends upon the distribution of solute, the strength of the crystal will also depend upon it because a portion of the applied stress for plastic deformation will be: where V is the volume of the crystal and E(E) is the energy change associated with the solute redistribution caused by the plastic strain, E. We expect T to equal zero for a crystal having a random arrangement of solute because the arrangement would remain random after plastic deformation. Likewise, we expect it to equal zero when the crystal is perfectly ordered because the motion of paired dislocations found in such crystals does not disrupt order. However, when short-range order exists or when long-range order is incomplete, plastic deformation will decrease the amount of order and additional work, proportional to the ordering energy, will be expended. Fisher&apos; estimated T for crystals having short-range order by assuming an interaction energy between neighboring atoms and estimating the change in the number of unlike neighbors as a dislocation moved through the crystal. (His analysis was limited and several workers2"6 have since given more complete ones.) Fisher minimized the importance of a strengthening mechanism of this type for paired dislocations in a structure having long-range order. ~ottrell,&apos; however, pointed out that T could be appreciable for ordered crystals having antiphase domains. He attributed the strengthening to the increase in surface energy of the domains as they were cut by paired dislocations. Ardley,&apos; in his test of Cottrell&apos;s theory, found that r for Cu3Au crystals obeyed the equation: for 1 > t where 1 is the domain size, t is the domain wall thickness, and y is the surface energy of an antiphase boundary. His experiments represent the classic confirmation of the strengthening mechanism proposed by Cottrell. However, the assumptions involved in using Cottrell&apos;s theory are valid only for large domain size in CU~AU,~"~ i.e., when Eq. [2] reduces to: For small domains, ~linn~ has questioned Ardley&apos;s assumption that order was complete, and, indeed, Stoloff and ~avies" fpnd it incomplete until a size of approximately lOOA was reached. Even when the order within a domain is complete, it is not obvious how one determines the appropriate value for I in a structure where domains vary in size and are irregularly shaped. The purpose of this paper is to estimate T without restrictions upon the degree of order and domain shape. Our major assumption will be the use of a generalization of the model proposed by Bethe" (the Ising model) for the internal energy. This will in fact allow us to combine the theories for strengthening by short-range order and by antiphase domains into a single, general formalism. We will use the results to estimate the variation in strength of Cu3Au crystals with long-range order8 and the variation in flow stress of FeCo crystals with quench temperature.12&apos;13 INTERNAL ENERGY For simplicity, we restrict our considerations to those binary solid solutions which can be described as an arrangement of atoms on a Bravais lattice. An atom site will be indexed by three numbers (PI, pz, p3) determined by the vector: from the origin fixed at atom (0, 0, 0) to the atom site where a&apos;, an, and a, are the lattice translation vectors. We write: For the energy of the crystal where pi(p) is the probability (either zero or one) of finding an atom of type i (i = 1, 2) at site (p), which is shorthand for (pl, pz, p3) and pj(p + r) is that for an atom of type j (j = 1, 2) at the site (p + r), which is shorthand for (pl + rl, The coupling parameter, resents the energy associated with the pair Pi(p), Pj(p + r). The crystal is assumed large enough so that surface effects can be neglected; therefore, trans-lational and inversion symmetry require the coupling parameters to obey the relations

Jan 1, 1969

By McHenry Mosier

MeRcuRy is one of the strategic metals of which the supply has been raised from critical uncertainty to more than enough for essential demands. Work by the Bureau of Mines has contributed substantially to increased production of mercury in the United States and to consequent accumulation of Government stocks. Other contributing factors have been higher prices for mercury and Government loans to operators. The Bureau has undertaken 13 exploration projects, 10 of which have been completed. This work has comprised 28,376 ft. of several types of drilling and 23,798 lin. ft. of surface trenching, and has indicated commercial ore containing 34,800 flasks of mercury and marginal ore containing 26,200 flasks, a total of 61,000 flasks; equivalent, respectively, to domestic production for 8 months, 6 months, and 14 months. As Government stocks are now adequate, domestic production (currently at the rate of 50,000 flasks per year) is gradually being curtailed through Government control of labor and operating supplies. Introduction Mercury was one of the seven metals designated as strategic by the Army and Navy Munitions Board in 1939, when Congress appropriated funds for the investigation of domestic sources of supply of war minerals. The Bureau of Mines immediately started a limited search for strategic minerals, but the first mercury project was not begun until December 1940. The U. S. Geological Survey assisted in the search for cinnabar by contributing information on domestic mercury deposits, preparing maps, and making geological studies of exploration projects. The present high rate of production of mercury in the United States was encouraged by the increase in price to $196 per flask at New York (Fig. I) and Government loans to operators for mine development and plant construction. The Bureau of Mines has issued, for restricted distribution subject to wartime controls, 13 War Minerals Reports on individual mercury deposits (listed in appendix A). In March 1942 it also published a Progress Report of the Metallurgical Division, R. I. 3627, Cinnabar-reduction Plants of the Southwestern Arkansas Quicksilver District. Uses of Mercury Mercury and its compounds have more than 3000 uses. Its principal use is as a catalyst in the manufacture of gases for chemical warfare; the next largest is in pharmaceuticals. Mercury is essential also for: (I) certain electrical apparatus, (2) industrial control instruments at many war plants, (3) munitions, including blasting caps, (4) insecticides in agriculture, (5) antifouling paint for ship bottoms, (6) dental preparations, (7) general laboratory use, and (8) amalgamation of free-milling gold ores.

Jan 1, 1949

By McHenry Mosier

MeRcuRy is one of the strategic metals of which the supply has been raised from critical uncertainty to more than enough for essential demands. Work by the Bureau of Mines has contributed substantially to increased production of mercury in the United States and to consequent accumulation of Government stocks. Other contributing factors have been higher prices for mercury and Government loans to operators. The Bureau has undertaken 13 exploration projects, 10 of which have been completed. This work has comprised 28,376 ft. of several types of drilling and 23,798 lin. ft. of surface trenching, and has indicated commercial ore containing 34,800 flasks of mercury and marginal ore containing 26,200 flasks, a total of 61,000 flasks; equivalent, respectively, to domestic production for 8 months, 6 months, and 14 months. As Government stocks are now adequate, domestic production (currently at the rate of 50,000 flasks per year) is gradually being curtailed through Government control of labor and operating supplies. Introduction Mercury was one of the seven metals designated as strategic by the Army and Navy Munitions Board in 1939, when Congress appropriated funds for the investigation of domestic sources of supply of war minerals. The Bureau of Mines immediately started a limited search for strategic minerals, but the first mercury project was not begun until December 1940. The U. S. Geological Survey assisted in the search for cinnabar by contributing information on domestic mercury deposits, preparing maps, and making geological studies of exploration projects. The present high rate of production of mercury in the United States was encouraged by the increase in price to $196 per flask at New York (Fig. I) and Government loans to operators for mine development and plant construction. The Bureau of Mines has issued, for restricted distribution subject to wartime controls, 13 War Minerals Reports on individual mercury deposits (listed in appendix A). In March 1942 it also published a Progress Report of the Metallurgical Division, R. I. 3627, Cinnabar-reduction Plants of the Southwestern Arkansas Quicksilver District. Uses of Mercury Mercury and its compounds have more than 3000 uses. Its principal use is as a catalyst in the manufacture of gases for chemical warfare; the next largest is in pharmaceuticals. Mercury is essential also for: (I) certain electrical apparatus, (2) industrial control instruments at many war plants, (3) munitions, including blasting caps, (4) insecticides in agriculture, (5) antifouling paint for ship bottoms, (6) dental preparations, (7) general laboratory use, and (8) amalgamation of free-milling gold ores.

Jan 1, 1949

By F. R. Morral, E. P. Miller

Hot-dipped heat-treated zinc coatings on sheet steel were examined with X-rays. The phases identified were compared with those listed in the modern literature 01 the zinc-iron system. The zeta (FeZn13) phase is shown to correspond to the phase found by Schueler (1925) in heat-treated zinc coatings. An investigation was undertaken to determine the phases present in hot-dipped heat-treated zinc coatings on steel sheets and wire. This kind of coating on wire was studied some years ago by Schuelerl by microscopic and chemical methods. He reported a new phase, FeZn10. Later, Clark and Stillwell,2 using X-ray crystal analysis, identified a new phase in ordinary galva. nized wire, which was assumed to be the FeZn10 phase. Since the extensive review of the iron-zinc alloys presented a few years ago,3 much new work has been published, some of which5-l6 was too late to be included in the recent edition (1939) of the American Society for Metals&apos; Handbook.4 Figs. 1 and 2 are reproductions of the latest iron-zinc diagram proposed by Schramml1 as a result of his investigations by microscopic, thermal, magnetic susceptibility and X-ray methods. Table 1 summarizes all the known published X-ray data of the phases Present. The solubility of iron in zinc has been determined by x-ray methods.10 In the same manner the homogeneity range of the P phase was studiedlo using the principle that the parameter of an intermetallic compound changes while the concentration of One of the constituents changes. Schramm10 has found some 80 alpha lines in X-ray powder photograms of phase d1, and from these he believes that this phase is related to the P phase. Previous investi-

Jan 1, 1941

By E. P. Miller, F. R. Morral

Hot-dipped heat-treated zinc coatings on sheet steel were examined with X-rays. The phases identified were compared with those listed in the modern literature 01 the zinc-iron system. The zeta (FeZn13) phase is shown to correspond to the phase found by Schueler (1925) in heat-treated zinc coatings. An investigation was undertaken to determine the phases present in hot-dipped heat-treated zinc coatings on steel sheets and wire. This kind of coating on wire was studied some years ago by Schuelerl by microscopic and chemical methods. He reported a new phase, FeZn10. Later, Clark and Stillwell,2 using X-ray crystal analysis, identified a new phase in ordinary galva. nized wire, which was assumed to be the FeZn10 phase. Since the extensive review of the iron-zinc alloys presented a few years ago,3 much new work has been published, some of which5-l6 was too late to be included in the recent edition (1939) of the American Society for Metals&apos; Handbook.4 Figs. 1 and 2 are reproductions of the latest iron-zinc diagram proposed by Schramml1 as a result of his investigations by microscopic, thermal, magnetic susceptibility and X-ray methods. Table 1 summarizes all the known published X-ray data of the phases Present. The solubility of iron in zinc has been determined by x-ray methods.10 In the same manner the homogeneity range of the P phase was studiedlo using the principle that the parameter of an intermetallic compound changes while the concentration of One of the constituents changes. Schramm10 has found some 80 alpha lines in X-ray powder photograms of phase d1, and from these he believes that this phase is related to the P phase. Previous investi-

Jan 1, 1941