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By C. H. Frick

Before presenting the main topic, as indicated by the title, this paper will give some of the high-spot history of the anthracite industry. Introduction The earliest recorded use of anthracite was in the year 1762, when a company of Connecticut pioneers discovered anthracite near the present city of Wilkes-Barre, Pennsylvania. In the early days of the industry, the coal was used only in large pieces, the smaller pieces being discarded to waste piles. As the output of the industry increased during the nineteenth century, uses were developed for somewhat smaller sizes down to and including pea coal. Early in the twentieth century, sizes smaller than pea, such as No. I and No. 2 buckwheat, were developed and used. Accumulations of piles from current mining operations were still increasing; that is, the smaller sizes were still being discarded. It was not until after World War I that preparation of the so-called steam sizes began commercially. This was largely No. 3 buckwheat, which is screened through a 3/16-in. round-hole screen and over a 3/32-in. or a 1/16-in. round-hole screen. Use of Smaller Sizes The earliest recorded experience in burning the small sizes of anthracite for steam production, other than in a previous small experiment, was in the year 1913, when a size known as "boiler fuel" was introduced—a mixture of rice and barley (No. 2 and No. 3 buckwheat). At that time, there was still no method known for burning the still smaller sizes. At the present time, various sizes down to and including No. 5 buckwheat are being prepared (Table I) from current mining and bank-reclaiming operations. The sizes of No. 4 and No. 5 buckwheat and smaller are generally being used for steam production in large boilers. The Pennsylvania Power and Light Co., following World War I, used 680,000 tons of anthracite per year, burned largely on stokers for production of steam, whereas for the year 1943 it used 1,940,000 tons of stoker sizes and 400,000 tons of smaller sizes for grinding and burning in pulverized form. This company has taken a very large part in the research and development of ways and means of burning these smaller sizes of anthracite, including the grinding of the very small sizes. This paper is particularly concerned with the latter feature.

Jan 1, 1949

By AIME AIME

WIDESPREAD interest in the better utilization of coal is indicated by the attendance of over seventeen hundred men interested in the pro- cessing and utilization of coal and its by-products, at Pittsburgh, Nov. 15 to 18. The conference was truly international in scope and of a scientific character, and must be considered a real success. There were dele- gates--official and unofficial-from America, Belgium, Canada, Czechoslovakia, France, Germany, Great Britain, Japan, Mexico, and Sweden. Several Federal and 28 State departments had representatives, also many colleges and universities, and many leading industrial and mining corporations throughout the country. A feature of the sessions was that papers were mostly read in full and attentively listened to, although in some cases they were of a technical nature. The proceedings were opened by the president of Carnegie Institute of Technology, Thomas C. Baker, who spoke of the importance of the conference and felt that without foreign cooperation it could not have been held. There was no need to apologize for the movement of Carnegie Institute of Technology in the matter. Coal is commanding attention in every part of the world; so is power; and coal will remain the chief source of power for generations to come. The coal chemist is working with the engineer, and nobody can forecast what developments there will be in fuel technology. This conference may be the turning point of fuel technology in America. The development and application of these new processes may be of great benefit to Pittsburgh.

Jan 1, 1926

[Billings Petroleum Section: Fraser M. Burback, chairman; N. J. Matthews, first vice-chairman; Charles B. Evans, second vice-chairman; and lion M. Madden, secretary-treasurer. Meets 3d Tues., Petroleum Club. California Coastal Section: Jack R. Severns, chairman.; Gilbert L. Jemmott, vice-chairman,- Jack A. Biren, secretary; and Robert L. Richardson, treasurer. Meets 3d Thurs.] [ ]

Jan 1, 1961

By N. P. Goss

Asterism appearing in X-ray Laue diagrams is an extremely sensitive index of changes in the internal structures of individual grains of polycrystalline metals. It indicates the existence of various forms of subboundary structure or subdivision within the grain. The present viewpoint is that the grain is made up of lattice blocks having substantially the same size and shape.l-4 When these blocks all assume exactly the same orientation, the crystal is perfect and asterism is absent. Cleaves and Thompson5 observed that the hardness of iron is virtually constant over a range of grain sizes. It is quite possible that the subboundary structure caused this, and that the latter is just as important as grain size itself. While the experiments reported here are not conclusive, they do support this viewpoint. Metals can, under certain conditions, be prepared entirely free from asterism, but this preparation does not necessarily require long heating or slow cooling, as will be shown here. In this paper a distinction is made between mosaic and distorted grain structures but the difference is only a matter of degree. In a previous paper9 it was shown that the grains can become distorted even during heat-treatment. The block structure exists inherently, even in a perfect crystal; the size and shape of these crystallites, or lattice blocks, varies, depending upon a number of factors. Goetz, for example: has shown that a metal before crystallizing from the molten state must go through a paracrystalline phase with oriented groups of atoms about 10-l4 to 10-l5 c.c., or 10-15 cm. in size. These crystallites, or blocks, appear to survive the most drastic cold-working, for it has been shown, and more elaborately by Wood's recent work," that cold-working cannot reduce the size of these crystallites smaller than of the order 10-5 cm. The interesting correlation brought out by the experiments of Goetz and Wood is that the block size after severe cold-working is of the same order of magnitude as the groups that formed in the metal just before crystallizing from the molten state. The work of Ewald and Rennenger17 and the now classical experiments of Darwin and James12,13 all strongly suggest the existence of a periodic structure of crystal. lites smaller than the grain itself. Related to this effect is the appearance of veinlike markings in the microstructures. Ammer-man and Kornfeld,16 in their experiments, did not observe any evidence of veining in specimens of alpha iron annealed below A3 and believed that veining was not due to impurities in the iron, as Northcott16 suggested; veining was observed by them only in specimens annealed above A3. Hanemann,16 Schrader and Tangerding found that annealing in hydrogen did not diminish veining and so it could not be caused by oxides. They concluded that veining was due to a slight difference in the orientation of ferrite lattice blocks. This viewpoint is well supported by the evidence presented here.

Jan 1, 1941

By N. P. Goss

Asterism appearing in X-ray Laue diagrams is an extremely sensitive index of changes in the internal structures of individual grains of polycrystalline metals. It indicates the existence of various forms of subboundary structure or subdivision within the grain. The present viewpoint is that the grain is made up of lattice blocks having substantially the same size and shape.l-4 When these blocks all assume exactly the same orientation, the crystal is perfect and asterism is absent. Cleaves and Thompson5 observed that the hardness of iron is virtually constant over a range of grain sizes. It is quite possible that the subboundary structure caused this, and that the latter is just as important as grain size itself. While the experiments reported here are not conclusive, they do support this viewpoint. Metals can, under certain conditions, be prepared entirely free from asterism, but this preparation does not necessarily require long heating or slow cooling, as will be shown here. In this paper a distinction is made between mosaic and distorted grain structures but the difference is only a matter of degree. In a previous paper9 it was shown that the grains can become distorted even during heat-treatment. The block structure exists inherently, even in a perfect crystal; the size and shape of these crystallites, or lattice blocks, varies, depending upon a number of factors. Goetz, for example: has shown that a metal before crystallizing from the molten state must go through a paracrystalline phase with oriented groups of atoms about 10-l4 to 10-l5 c.c., or 10-15 cm. in size. These crystallites, or blocks, appear to survive the most drastic cold-working, for it has been shown, and more elaborately by Wood's recent work," that cold-working cannot reduce the size of these crystallites smaller than of the order 10-5 cm. The interesting correlation brought out by the experiments of Goetz and Wood is that the block size after severe cold-working is of the same order of magnitude as the groups that formed in the metal just before crystallizing from the molten state. The work of Ewald and Rennenger17 and the now classical experiments of Darwin and James12,13 all strongly suggest the existence of a periodic structure of crystal. lites smaller than the grain itself. Related to this effect is the appearance of veinlike markings in the microstructures. Ammer-man and Kornfeld,16 in their experiments, did not observe any evidence of veining in specimens of alpha iron annealed below A3 and believed that veining was not due to impurities in the iron, as Northcott16 suggested; veining was observed by them only in specimens annealed above A3. Hanemann,16 Schrader and Tangerding found that annealing in hydrogen did not diminish veining and so it could not be caused by oxides. They concluded that veining was due to a slight difference in the orientation of ferrite lattice blocks. This viewpoint is well supported by the evidence presented here.

Jan 1, 1941

By C. H. Frick

BEFORE presenting the main topic, as indicated by the title, this paper will give some of the high-spot history of the anthracite industry. INTRODUCTION The earliest recorded use of anthracite was in the year 1762, when a company of Connecticut pioneers discovered anthracite near the present city of Wilkes-Barre, Pennsylvania. In the early days of the industry, the coal was used only in large pieces, the smaller pieces being discarded to waste piles. As the output of the industry increased during the nineteenth century, uses were developed for somewhat smaller sizes down to and including pea coal. Early in the twentieth century, sizes smaller than pea, such as No. I and No. 2 buckwheat, were developed and used. Accu¬mulations of piles from current mining operations were still increasing; that is, the smaller sizes were still being discarded. It was not until after World War I that preparation of the so-called steam sizes began commercially. This was largely No. 3 buckwheat, which is screened through a 3f 6-in. round-hole screen and over a 332-in. or a M 6-in. round-hole screen. USE OF SMALLER SIZES The earliest recorded experience in burning the small sizes of anthracite for steam production, other than in a previous small experiment, was in the year 1913, when a size known as "boiler fuel" was introduced-a mixture of rice and barley (No. 2 and No. 3 buckwheat). At that time, there was still no method known for burning the still smaller sizes. TABLE I.-Screen Sizes Used for Small Sizes of Anthracite [ ] At the present time, various sizes down to and including No. 5 buckwheat are being prepared (Table I) from current mining and bank-reclaiming operations. The sizes of No. 4 and No. 5 buckwheat and smaller are generally being used for steam production in large boilers. The Pennsylvania Power and Light Co., following World War I, used 680,000 tons of anthracite per year, burned largely on stokers for production of steam, whereas for the year 1943 it used 1,940,000 tons of stoker sizes and 400,000 tons of smaller sizes for grinding and burning in pulverized form. This company has taken a very large part in the research and development of ways and means of burning these smaller sizes of anthracite, including the grinding of the very small sizes. This paper is particularly concerned with the latter feature.

Jan 1, 1946

By F. A. Crossley

The additions: o, Sn, Zr, Cb, Mo, and V were studied for their effects on the a/a + Ti3A1 boundary of Ti-A1 base ternary alloys. These additions were chosen because of their importance to commercial titanium alloy practice—oxygen as the major impurity (in terms of influence on mechanical properties) and the others as major alloying additions. The composition and temperature ranges of investigation varied according to the system as shown in Table I. The principal means of investigation was light-microscopy. The basis of the ternary studies was the recently determined titanium-rich end of the Ti-A1 system.' MATERIALS, METHODS, AND PROCEDURES Ingots were prepared in 15 g size for all alloys except those of the Ti-Al-Mo and Ti-A1-V systems which were prepared in 20 g size. These alloys were prepared from high-purity, electrolytically refined titanium obtained from the Bureau of Mines, Boulder City Metallurgical Laboratory, Boulder City, Col., and Chicago Development Corp., Riverdale, Md., for the 15 g and 20 g ingots, respectively. The alloying additions were obtained from commercial sources, and were at least of 99.9 pct purity, except the V-15 wt pct A1 master alloy for vanadium additions. This alloy was of 98.2 pct purity; the major impurities were 0.37 wt pct Fe and 0.38 wt pct Si. The ingots were prepared by multiple melting in a nonconsum-able-electrode arc furnace. The ingots were covered with Markal coating "CR-T22" (Markal Co., Chicago) to protect them from scaling. Markal coating is applied as a slurry of solids in a volatile carrier liquid. The coated article is air dried. Upon heating to the hot working temperature the coating fuses to form a glassy, protective film. The ingots were heated to 1000°C and rolled to 0.16 in. thickness, reheating after each pass. The glassy film was removed by sand blasting. Ten mils were removed from all surfaces by grinding and/or pickling (3 pct HF, 30 pct HN03, balance water). Grinding was always followed by pickling to remove traces of the grindmg medium. Hydrogen removal was accomplished by vacuum annealing at 1000°C for 2 hr to a final pressure of about 0.02 µ Hg. This was followed by annealing in evacuated Vycor bulbs (800°C, 2 hr, ice brine quenched (IBQ)) in order to maximize ductility. The materials were then lightly pickled and cold rolled to 0.12 in. thickness or cracking, whichever occurred first. After rolling, 1/2 by 1/4 in. specimens were cut for the equilibration anneals given in Table 11 and carried out as previously described.1 Final polishing of the specimens for metallographic examination was done by electrolytic means. Specimens were first examined without etching under bright field and polarized light illumination, for this is the only means of detecting the "two-phase" phenomenon.1,2 The term "two-phase syndrome" refers to Ti-A1 al-loys which appear on the bases of their chemical, phys-ical, and mechanical properties, to be two-phase, but are actually single phase and inhomogeneous in composition. Since processing and heat treatment of the alloys of the first group were completed before the two-phase syndrome was discovered, a number of the specimens were found to exhibit this phenomenon—80 pct of those of the Ti-Al-Zr system, 5 pct of those of the Ti-Al-Sn system, 30 pct of those of the Ti-Al-Zr system. The affected specimens were homogenized by heating above the ß transus temperature and quenching. The heat treatment and working schedules to accomplish this are given in Table 111. After rolling, specimens were pickled (3 pctHF, 30 pct HNO3 in water) to remove 1 to 2 mils from the

Jan 1, 1970

By G. R. Leverant

RECENT investigations1,2 of the low-cycle fatigue behavior of pure copper under strain cycling conditions have shown that a unique saturation stress level is eventually attained for each value of applied plastic strain amplitude. The dislocation substructure of copper at the saturation stress level is in the form of cells whose diameter decreases with increasing saturation stress level, i.e., plastic strain amplitude. In addition, both the saturation stress level and the cellular substructure are completely reversible. That is, the saturation stress level and accompanying cell size are determined solely by the present conditions of testing and are, therefore, independent of any previous cyclic history. The mechanical and substructural reversibility observed in pure copper, which has a relatively high stacking fault energy, is not observedz for Cu-7.5A1 which has a much lower stacking fault energy. This implies that easy cross slip (wavy slip) is a prerequisite for reversible fatigue behavior. A dispersion of fine, nondeformable particles of a second phase in a metal matrix tends to stabilize substruc- tures introduced by forming operations during subsequent elevated-temperature heat treatments.3 This raises the question as to whether a finely dispersed second phase can induce an element of irre-versibility into the cyclic deformation behavior of a wavy slip material at room temperature, due to partial stabilization of the initially introduced substructure. Since nickel has a higher stacking fault energy than copper,6 pure nickel should be characterized by cyclic reversibility. Therefore, TD-nickel* (Ni-2ThO.r) was

Jan 1, 1968

By C. W. Spencer, B. F. Addis, G. H. Bishop, C. A. Steidel

STUDIES of the inter granular attack of metals by liquids have generally been confined to polycrys-talline specimens. This note reports the results of preliminary studies of the penetration of bismuth-rich Ni-Bi liquids into oriented bicrystal specimens of nickel. It is found that isothermal penetration follows a parabolic rate law and shows a definite anisatropy with respect to direction on the grain boundary surface. Nickel bicrystals containing < 100> tilt boundaries were grown using the Czochralski method. Relative misorientation of the parent crystals was controlled to ± 1deg. The boundaries are straight in the growth direction, i.e., the common <100>, and generally straight in the transverse direction, as shown in Fig. 1. The starting material, Inco HPM grade nickel was contained in a recrystallized alumina crucible and maintained under argon. Bicrystals typically contain 30 ppm C, less than 10 ppm S, O, N, and 50 ppm residual metallics, principally iron and silicon. Specimens, as schematically illustrated in Fig. l(c),were cut from bicrystal ingots using a thin water-cooled abrasive wheel. To insure removal of all residual strain, which accelerates the penetration, specimens were round through 600 grit silicon-carbide, chemically polished, and annealed for 4 hr at 1375°C under argon. The procedure described by Cheney et al.1 for exposing specimens to

Jan 1, 1962

By R. H. Richards, A. E. Woodward

In Rittinger&apos;s Aufbereitungskunde of 1867 occurs (p. 195) the following table, which shows the rate of falling in water of fragments of minerals, of irregular shapes and of five different specific gravities: Diameter of particles in millimeters. 10 8 6 4 3 2 1 .5 Sp. Or. Velocity in meters per second. Auriferous silver, 16..9 .8 .7 .57 .5 .4 .29 .20 Galena,. ..7.5 .62 .55 .48 .39 54 .28 .20 .14 Pyrites,. ..5.0 .49 .43 .38 .30 .26 .22 .15 .10 Quartz,. ..2.6 -30 .27 24 .19 .17 .14 .10 .07 Coal,. ..1.3 .13 .12 .10 .08 .07 .06 .04 .03 With the purpose of extending this valuable table, to cover a larger number of minerals and sizes of each mineral, and of making it more easy of application in deciding upon a sieve-scale for any group of minerals, we have prepared the curves of velocity of fall of bodies in water shown in Plates I., XI., 111. and IV., using Rittinger&apos;s formula V= 2.44d(8 —1) where V= velocity in millimeters per second. " D = diameter of particles in meters. " 8 = specific gravity of the mineral. These curves embrace a large number of specific gravities, and for each specific gravity the relation of the diameter of the mineral particle to the velocity of its fall in water is given for all diameters and velocities used in practice. The second diagram is an enlargement of the lower left-hand corner of the first, the third bears the same relation to the second, and in like manner the fourth to the third. Plate I, therefore, covers the work of the coarsest jigging 2 inches in diameter; and under

Jan 1, 1890

By F. J. Plecity, J. T. Michalak, W. C. Leslie

Isothermal recrystallization and grain growth in zone- and vacuum-melted irons and Fe-Mn alloys, up to 0.60 pct Mn, were studied in the range 480° to 650° C, after 60 pct cold reduction. In initial stages, rate of grain growth and rate of recrystallization of iron decrease with time. The recrystallization is typical of a growth-controlled process, and rate of growth is determined by the extent of recovery. Mn decreases rates of growth and of recrystallizatzon. The recrystallization process changes at about 0.30 pct Mn and nucleation may become time-depetzdet~t. In recent years, considerable effort has been expended in determining the effects of solute elements on recrystallization and boundary migration in fcc metals. The results have indicated that the effects produced by single solute additions are dependent upon both the element added and its concentration.&apos;-&apos; In contrast, there have been very few attempts to determine the characteristics of recrystallization and boundary migration in high-purity bcc metals, especially after heavy deformation, and the effects thereon of single solute elements.9-11 This study was undertaken to determine the recrystallization characteristics of various "high-purity" irons and the effects of manganese additions at two levels of base purity. It was hoped that the information obtained would improve our understanding of the recrystallization of pure metals and aid in formulating a theory for the effect of solute elements. The interest was not entirely academic, for the annealing of low-carbon steels, which is of very great commercial importance, is but poorly understood. MATERIALS The compositions of the irons and iron-manganese alloys used are listed in Table I. The zone-melted iron and Fe-Mn alloys were made by Battelle Memorial Institute. Iron S-1 was arc-melted in a water-cooled steel mold in an argon atmosphere. The ingot was forged into a bar, then given two horizontal zone-refining passes in an alumina boat. Iron V-4 was treated in a similar manner, but was not zone-refined. The iron for the zone-melted Fe-Mn alloys was induction melted in vacuum in MgO crucibles and cast into alumina molds. The ingots were forged into bars, machined to shape, and a groove milled down one side of each. The best available electrolytic Mn was placed in the grooves, and the bars were zone melted. The vacuum-melted Fe-Mn alloys were induction melted in this Laboratory in MgO crucibles and poured into cast-iron molds. Iron V-5 was purchased from National Research Corp. in the form of a small vacuum-cast ingot. The low-carbon steel was made by induction melting in air at the U.S. Steel Corp. Applied Research Laboratory. The history of the materials prior to the final cold reduction differed; these details are given in the Appendix. The penultimate grain size of the principal materials was kept in the range ASTM 2 to 4, except for the low-carbon steel. PROCEDURES The cold work prior to the final recrystallization anneal was kept constant at 60 pct. It is known that rolling procedure can influence the kinetics of recrystallization of ironI2; therefore, all specimens were rolled in one direction only, between clean,

Jan 1, 1962

Would you give us a short biographical sketch including your birthplace, education and current activities? I was born Jan. 16, 1920 in Minneapolis, Minnesota, and lived there the first 22 years of my life. I also spent quite a bit of time on a farm about fifty miles north of Minneapolis owned by relatives. During the Depression, we lived off of ten cows and about fifty chickens. I&apos;m a full-blooded Swede all along the line, and I&apos;ll be the last one in my family since my wife is not of Swedish descent. I attended Macalester College, a small school in St. Paul, to study for the ministry originally. However I soon realized that I really didn&apos;t have the talents for the ministry and I could probably do as much or more in a field where I did have some talent.

Jan 3, 1974

By S. Feuerstein

THE influence of environment on the mechanical properties of metals has been extensively studied and documented.&apos; Most investigations have dealt with an interaction between a particular environment and a specific metal surface and the concomitant change in bulk mechanical behavior. Typical contributing media are oxide and metal film:;, electrolytes, and other surface-active agents. In the last category fall controlled gaseous environs (i.e., pressure or vacuum). Most vacuum exposure experiments prior to 1963 were conducted at pressures s>10-6 torr and elevated temperatures, or in such a manner as to prolong the exposure (e.g., by stress-rupture, creep, and fatigue). Little attention has been given to vacuum environment effects on the mechanical behavior of metals subjected to simple uniaxial deformation at room temperature. Test times and temperatures were assumed too ineffective as far as bulk changes were concerned. Further, the contribution of surface effects to the bulk mechanical behavior of metals was considered minimal. Under vacuums of the order of 1.0- 8torr and higher, molecular densities and, consequently, the rate of monolayer formation are such that exposures from seconds to days would be required for complete gas coverage. Thus, atomically clean surfaces created under ultra-high vacuum could conceivably maintain their cleanliness for time intervals orders of magnitude greater than at higher pressures. The influence of this unusual type of environmental surface phenomenon on the short-term bulk mechanical behavior of aluminum was first observed by Krame and Podlaseck in 1963.&apos; kin equivalent effect was reported for magnesium by Williams and Nelson.3 It was concluded from these studies2,3 that vacuum and, consequently, the monolayer formation rate of the oxide, were responsible for the described changes in flow behavior. The presence of an oxide layer impedes dis- I) EXPERIMENTAL DATA: MOLYBDENUM The tensile behavior of molybdenum was investigated by the author4-6 at ambient temperature over a range of pressures from 760 to 10-10 torr. These studies revealed that the flow behavior of the bulk specimens (0.200 in. diam by 2 in. gage length) was independent of pressure on sintered (0.062 mm grain size) and arc-cast polycrystals (0.012 to 0.149 mm grain sizes) and single crystals. Since the specimens were relatively large in size, it was assumed that any flow behavior effect would be surface-limited because of the short-term deformation procedure. Strain-rate-change experiments performed to determine the activation volumes for individual specimens at 760 to 10- 10 torr further indicated that the surface flow contribution was either minimal or zero, contrary to the findings of Shen el a1.7 on aluminum. Although the flow behaviors did not change, specimen ductility did change. For the sintered material at a strain rate of 4.2 x 10-4, specimen ductility was -9 pct higher at l0- 10 torr than at atmospheric pressure (dry nitrogen). A more comprehensive investigations on this same material revealed a distinct pressure dependence, Fig. 1. Intermediate and atmospheric pressure tests were obtained by backfilling the system from l0- 10 torr with extra dry, prepurified nitrogen. Other environments (air and purified argon) were also utilized for the 760 torr experiments; the results were essentially the same as those for dry nitrogen atmospheres. Departure from the fracture strain values obtained at 760 torr takes place in the vicinity of l0-6 torr, as indicated by the scatter band; a noticeable ductility increase is apparent at l0-8 and 10-10 torr.

Jan 1, 1970

By O. Nomland

The work of The Bahrein Petroleum Company, Ltd., on Bahrein Island consisted mainly in continuing development work and prospecting previously reported. The exploratory work, however, has been greatly minimized and new wells are being drilled, chiefly for the development of larger production; 20 wells had been completed by the end of 1935 and 8 were being drilled. In addition to what has been referred to as the &apos;&apos;main pay," two deeper productive horizons have been discovered, which apparently will greatly increase the potential of the field although the areal extent of this lower production has not yet been determined. The proven acreage of the "main pay" is more than 12,500 acres. Current production (principally from the upper horizons) is about 13,400 bbl. a day. The construction of a 10,000-bb1.-a-day refinery has begun and is to be in operation by July, 1936. It is expected that the capacity will be considerably increased at a later date. The construction of office buildings and a permanent camp has been almost completed. In Saudi Arabia the California Arabian Standard Oil Co., a wholly owned subsidiary of the Standard Oil Company of California, spudded in a well in April, 1935, near the village of Dammam, on the Persian Gulf coast of A1 Hasa. Although several important showings of high-gravity oil and considerable gas have been found, the well is not yet considcred a commercial producer. Dammam well No. 2 has been started farther south on the same structure. A great deal of reconnaissance and some detailed geological work has been completed during the last three field seasons. In order to overcome difficulties of transportation over the desert sand, unusual methods have been used. The parlies penctrating the interior by the use of automobiles and trucks have been supplied with gasoline and provisions by caravans of camels. Mail and supp1ies of lighter weight urgently needed have been carried to the field men by an airplane operated by the geological division of the company. Each party has been supplied with a radio receiving and transmitting set to keep in contact with the airplane as well as with geological headquarters at Jubail on the coast of A1 Hasa.

Jan 1, 1936

By O. Nomland

The work of The Bahrein Petroleum Company, Ltd., on Bahrein Island consisted mainly in continuing development work and prospecting previously reported. The exploratory work, however, has been greatly minimized and new wells are being drilled, chiefly for the development of larger production; 20 wells had been completed by the end of 1935 and 8 were being drilled. In addition to what has been referred to as the &apos;&apos;main pay," two deeper productive horizons have been discovered, which apparently will greatly increase the potential of the field although the areal extent of this lower production has not yet been determined. The proven acreage of the "main pay" is more than 12,500 acres. Current production (principally from the upper horizons) is about 13,400 bbl. a day. The construction of a 10,000-bb1.-a-day refinery has begun and is to be in operation by July, 1936. It is expected that the capacity will be considerably increased at a later date. The construction of office buildings and a permanent camp has been almost completed. In Saudi Arabia the California Arabian Standard Oil Co., a wholly owned subsidiary of the Standard Oil Company of California, spudded in a well in April, 1935, near the village of Dammam, on the Persian Gulf coast of A1 Hasa. Although several important showings of high-gravity oil and considerable gas have been found, the well is not yet considcred a commercial producer. Dammam well No. 2 has been started farther south on the same structure. A great deal of reconnaissance and some detailed geological work has been completed during the last three field seasons. In order to overcome difficulties of transportation over the desert sand, unusual methods have been used. The parlies penctrating the interior by the use of automobiles and trucks have been supplied with gasoline and provisions by caravans of camels. Mail and supp1ies of lighter weight urgently needed have been carried to the field men by an airplane operated by the geological division of the company. Each party has been supplied with a radio receiving and transmitting set to keep in contact with the airplane as well as with geological headquarters at Jubail on the coast of A1 Hasa.

Jan 1, 1936

By N. M. Raju, B. Singh

The paper seeks to present the results of experimentation in room and pillar stopes with different ground conditions to determine the safe working span. In the experimental stopes, ground movement was monitored with gradual widening of the room span. The field measurements included closure between the stope walls and the extent of ground movement in the hangwall using borehole extensometers. hock bolting was used as an exclusive support system which enabled introduction of scrapers for improving productivity. In one nine, phosphate bed, 3 to 3.5 m thick dipping at 45O and overlaid by weak laminated shale, was worked at shallow depth of cover. h the experimental panel, five s topes were worked with spans varying from 5.5 to 7 m. In the second mine, the chalcopyrite orebody up to 6 m in thickness dipping at 25 - 30" was worked at a depth of 1100 m. The hangwall consisted of fairly competent schistose rocks and therefore 10 to 15 m wide spans could be experimented. The field measurements confirmed that in the phosphate mine with weak shale roof, 7 m span could be safely worked with subsequent caving of the bolted roof. In the copper mine, 15 m span could be worked and the stopes required subsequent backfilling for better ground control.

Jan 1, 1983

By Kenneth A. Gutschick, Robert S. Boynton

Lime has become a general and loosely used term to denote almost any kind of calcareous material or finely divided form of limestone or dolomite, as well as burned forms of lime. However, according to Webster, lime is only calcined limestone (known as quicklime, unslaked lime, or calcium oxide). It also embraces the secondary product of quicklime, i.e., hydrated lime or slaked lime (calcium hydroxide). There are two basic types of limestone used for lime manufacture-high calcium and high magnesium (dolomitic). The dolomitic quicklimes and hydrated limes correspond to their "high calcium" counterparts. The only difference is that the dolomitic types are a combination of the elements calcium and magnesium, in varying percents, whereas high calicum limes contain less than 5% MgO down to 1/2%. In either case a pure form of limestone of at least 97% combined carbonate content is needed to make salable lime, barring a few exceptions. The calcination of both types is diagrammed chemically as follows: [ ] In the foregoing reversible reactions the limestone is burned (calcined) in lime kilns, with the carbon dioxide content of the stone expelled as a gas. The weight loss during calcination of pure high calcium limestone is 44%; with equimolecular dolomitic limestone, the weight loss is 48%. Since lime has a strong affinity for CO_, particularly if moisture is present, it will readily revert to its original carbonate form. This occurs when quicklime "air-slakes" and adsorbs CO.. from the air. Thus, quicklime is perishable and should be stored in dry, water-tight areas. Depending upon the type of kiln used and the physical structure of the stone, the size of the quicklime may range from sandlike granules to 8 in. lumps. However, pebble sizes ranging from 1/4 in. to 2 in. are the most common. Screened quicklime fines are also com¬pressed (pelletized) into 1 in. pellets. For some purposes ground or pulverized forms of quicklime are used, ranging from No. 10 mesh to dust. Generally a pebble of quicklime is about the same size as the pebble of limestone before calcination (perhaps shrinking slightly). A more stable form of lime is hydrated lime. This is obtained by adding water to quicklime, slaking it into a dry, fine, subsieve size white powder. Because its affinity for moisture has been satisfied, it is not vulnerable to further moisture like quicklime. However, it has the same strong affinity for CO_. The following reversible chemical reactions illustrate how hydrated lime when heated (or dehydrated) can revert to the original oxide form:

Jan 1, 1975

By T. A. Rickard

Flaubert, as we know, laid stress on the selection of the right word, le mot juste, the precise epithet, the word that belongs to the thing. A sentence, or even a paragraph, may be spoiled by the use of a word that is not proper, that does not fit or is foreign to the meaning intended. An Australian mining expert is reported to have said: You have a property of considerable value, and what I saw warrants a good development of very rich cubicular galena, with gossan intermixed. &apos;Cubicular&apos; means `belonging to a small bedroom&apos;, a `cubicle&apos; being a sleeping compartment. He meant `cubic&apos;, of course. This is a malapropism, and reminds me of the lady from Chicago that, on her return from Europe, said how much she had enjoyed the rural parts of France, because, among other things, it was "so delightful to hear the French pheasants singing the mayonnaise to the tune of the Los Angelus". It is impossible to amalgamate coal-tar thoroughly with the pulp in the agitating-tank. In metallurgy, `amalgamate&apos; refers to the combination of mercury with one or both of the precious metals, forming an amalgam, which is an alloy of mercury with another metal. It differs from other alloys, such as brass or bronze, in being made without the aid of heat, inasmuch as mercury is molten at the ordinary temperature. The word comes to us from the Greek. through Old French and means `something soft&apos;. It is a mistake to use technical terms, having a specific meaning, for purposes that are foreign to that meaning. The writer of the quotation is not discussing any combination of metals; he is dealing with the physical process of mixing and is using &apos;amal-

Jan 1, 1931

By GUY C. RIDDELL, Donald M. Liddell

THE electronic arts today constitute the outstanding development in the field of rare metals, if not indeed in the arena of scientific progress at large. The year 1930 may become known as the year in which the electronic tube took hold of the wheels of industry; it is the year in which the tube&apos;s emancipation from the art of communication was proclaimed. The little tube which made a $500,000,000 industry out of a vacuum has now been applied to mining, manufacturing, transportation, chemistry, and other industries. Not many appreciate the extensive utility that e1ectroni.t tubes have already found in transportation, where they control the speed and security of express trains, as well as operate traffic lights on important highways-in the case of the Detroit-Windsor bridge counting the traffic and instantly turning the reports into the superintendent&apos;s office some distance away. In an Ohio steel mill, ten-ton ingnts &apos;rash back and forth through the rolls, reversed by their own shadows. The vacuum tube also starts, stops, and levels, fast passenger elevators.

Jan 1, 1931

By R. J. Charles

SEARCH for a consistent theory to explain the relationship between energy input and size reduction in a comminution process has accumulated, over the years, an enormous amount of plant and laboratory data. Although some correlation of these data has been possible for purposes of engineering design and for the advancement of research in fracture, there is still great need of a means of predicting behaviour of a solid when it is reduced in size by mechanical forces. The best known hypotheses proposed to describe the energy-size reduction relationships in crushing and grinding stem from a common origin. The present article analyzes problems of comminution in the light of the precepts of this origin. Its object is to reconcile points of difference between these well known hypotheses and to present relationships more widely applicable to comminution studies. Theoretical Considerations: Most existing relationships between energy and size reduction of a brittle solid stem from a single, simple, empirical proposition.&apos; Although this proposition can be demonstrated by observation and experiment, no theoretical derivation is yet possible. Mathematically, the proposition may be stated as follows: dE = -Cdx/xn [1] where dE = infinitesimal energy change, C = a constant, dx = infinitesimal size change, x = object size, and n = a constant. Eq. 1 states that the energy required to make a small change in the size of an object is proportional to the size change and inversely proportional to the object size to some power n. No stipulations are placed on the exponent n in either magnitude or sign. In 1867 Rittinger2 postulated that the energy required for size reduction of a solid would be proportional to the new surface area created during the size reduction. As far as can be determined there is as yet no physical basis for Rittinger&apos;s hypothesis. Rittinger&apos;s hypothesis can be stated mathematically as follows: E, = K(oa-a-0 . [2] Er = energy input per unit volume, K = a constant, <ti = initial specific surface, and o2 = final specific surface. In the size reduction of particles of size x, to particles of another smaller size, x2, Eq. 2 becomes the well known relation: ET = K&apos; {l/x2-l/xx) [3] where K&apos; is a constant. Eq. 3 may be arrived at from the proposition given in Eq. 1 by integrating and by assigning a value of 2 to the exponent n. J dE = J - C dx/x2 E = Kt (1x - 1x) where K&apos; = C. In 1885 Kick3 proposed the theory that equivalent amounts of energy should result in equivalent geometrical changes in the sizes of the pieces of a solid. For example, if one unit of energy reduced a number of equal-sized particles to particles of one half the size, then the same amount of energy applied to the particles resulting from the first test should result again in a size reduction of one half or a final size one quarter the original size. The Kick concept may be expressed as follows: Ek = K" log x1/x2 [41 K" = a constant and E, = energy per unit volume. The expression for Kick&apos;s law may be arrived at by again integrating Eq. 1 and in this case assigning a value of 1 to the exponent n. dE= J - C dx/x Eh = - C In {x/x2) = K" log (x,/x,) where K" = 2.3 C. Application of Kick&apos;s and Rittinger&apos;s laws to comminution has met with varied success. Gross and Zimmerley4 and Piret5 have shown that Rittinger&apos;s equation applies under certain conditions of experimentation. Walker and Shaw6 express the belief that in metal turning and shaping and in grinding of both metals and minerals the production of very fine particles (less than lP) follows Kick&apos;s hypothesis, whereas Rittinger&apos;s concept is valid for the size reduction of coarse particles. For the practical case of crushing and grinding, however, neither of the above hypotheses has received general acceptance. Bond&apos; has lately proposed that since neither Kick&apos;s nor Rittinger&apos;s hypotheses seem correct for plant design work, an energy-size reduction relationship somewhere between the two would be more applicable. The fundamental statement of Bond&apos;s work

Jan 1, 1958