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By Takahide Wakamatsu, Shigeru Mukai

Fundamental investigations were made on the treatment of slime and the chrysocolla flotation, both of which are urgent problems to be solved in copper oxide mineral flotation. Unfavourable effects of slime on flotation are caused by the slime adsorption at the air/liquid Interface as well as the slime coating on the mineral surface. The adsorption of slime at the air/liquid interface was measured by using various kinds of slime particles. As a consequence, goethite, bentonite and talc tended to adsorb markedly at the interface. As a desliming method, slime flotation with a polymer flocculant such as polyethylene-oxide prior to the ordinary copper oxide flotation was found to be effective. The use of both a copper-avid organic reagent and an alkyl xanthate was examined for a selective collection of chrysocolla through xanthate adsorption tests, chrysocolla float- abllity tests and flotation tests for synthetic and natural ore. The copper-avid reagents used were salicylaldoxime, 8- hydroxyquinollne and benzoin-a-oxime. As a result, the ad- sorption of higher xanthate such as amyl xanthate on chrysocolla as well as the chrysocolla-to-air bubble attachment was increased by the presence of a copper-avid reagent under suitable reagent addition and pH of pulp. Flotation tests for synthetic and natural ores confirmed that chrysocolla could be floated sufficiently and selectively with a copper- avid reagent like 8-hydroxyquinoline or salicylaldoxime with its subsequent collection by amyl xanthate.

Jan 1, 1976

By D. O. Wyble, L. O. Bacon

THERE has been considerable speculation among mining geologists and mining men in general as to the relative merits of gravity methods in iron-ore exploration. Most of the investigations which have been carried out in recent years have been done by mining companies, and few if any of the results have been published. Three gravity surveys have been made in the Iron River-Crystal Falls area,' " one by the U. S. Bureau of Mines, with inconclusive results, and the other two by Radar Exploration Co. for the Cleveland-Cliffs and the M. A. Hanna companies, with results not known to the writers. Both the last-mentioned surveys were detailed investigations, the stations being spaced as close as 10 ft along traverses,' and were made to determine the feasibility of locating iron ore by gravitational methods. Because of the presence of a large body of ore already extensively drilled, Dr. Harold L. James of the U. S. Geological Survey, Iron River, Mich., suggested that a further test of gravitational methods of exploration be made in the Round Lake area of Iron County, see Figs. 1 and 2. This survey indicated a considerable regional gradient and led to a study of the surrounding gravity field and its relation to the major structural features of the syncline within which the iron formation lies. The southwestern part of Iron County presents a series of hills and hollows elongated in a roughly north-south direction. The bedrock topography is of pre-glacial origin. Relief is moderate; a maximum elevation difference of approximately 350 ft was observed during the survey. Major drainage is dendritic with the larger streams: the Brule to the south, the Paint to the north, and the Iron in the central part. Hills are thickly grown with hard- woods, and lowland areas, not under cultivation, are usually covered by second-growth softwoods. The area covered in this paper includes the southern half of Iron County, Mich., with a deep synclinal basin occupying the central part of the area, and the southeast corner of Gogebic County, immediately to the west of Iron County. The upper Huronian iron formation, slates, and graywackes which form the synclinal basin rest upon a greenstone basement. The basin has not been completely outlined by exposures, drill records or other means, as outcrops are scarce and the thick mantle of glacial drift makes geological investigations extremely difficult. Glacial drift varies in depth up to 300 ft or more. The drift is usually thickest under the hills and is thinnest in the depressions and along drainage courses where most of the bedrock exposures occur. The area over which gravity investigations were made is almost, entirely covered by glacial material. Bedrock of the basin consists of a complexly folded series of iron formation, slates, and graywackes. One of the series of slates has a high magnetic susceptibility due to the fine-grained magnetite it contains. This formation can be detected readily. by magnetic methods and provides a marker horizon which can be easily followed. The magnetic slates are stratigraphically above the iron formation, and much of the geological interpretation of the area is based upon the magnetic anomalies they produce.

Jan 1, 1953

By L. O. Bacon, D. O. Wyble

THERE has been considerable speculation among mining geologists and mining men in general as to the relative merits of gravity methods in iron-ore exploration. Most of the investigations which have been carried out in recent years have been done by mining companies, and few if any of the results have been published. Three gravity surveys have been made in the Iron River-Crystal Falls area,' " one by the U. S. Bureau of Mines, with inconclusive results, and the other two by Radar Exploration Co. for the Cleveland-Cliffs and the M. A. Hanna companies, with results not known to the writers. Both the last-mentioned surveys were detailed investigations, the stations being spaced as close as 10 ft along traverses,' and were made to determine the feasibility of locating iron ore by gravitational methods. Because of the presence of a large body of ore already extensively drilled, Dr. Harold L. James of the U. S. Geological Survey, Iron River, Mich., suggested that a further test of gravitational methods of exploration be made in the Round Lake area of Iron County, see Figs. 1 and 2. This survey indicated a considerable regional gradient and led to a study of the surrounding gravity field and its relation to the major structural features of the syncline within which the iron formation lies. The southwestern part of Iron County presents a series of hills and hollows elongated in a roughly north-south direction. The bedrock topography is of pre-glacial origin. Relief is moderate; a maximum elevation difference of approximately 350 ft was observed during the survey. Major drainage is dendritic with the larger streams: the Brule to the south, the Paint to the north, and the Iron in the central part. Hills are thickly grown with hard- woods, and lowland areas, not under cultivation, are usually covered by second-growth softwoods. The area covered in this paper includes the southern half of Iron County, Mich., with a deep synclinal basin occupying the central part of the area, and the southeast corner of Gogebic County, immediately to the west of Iron County. The upper Huronian iron formation, slates, and graywackes which form the synclinal basin rest upon a greenstone basement. The basin has not been completely outlined by exposures, drill records or other means, as outcrops are scarce and the thick mantle of glacial drift makes geological investigations extremely difficult. Glacial drift varies in depth up to 300 ft or more. The drift is usually thickest under the hills and is thinnest in the depressions and along drainage courses where most of the bedrock exposures occur. The area over which gravity investigations were made is almost, entirely covered by glacial material. Bedrock of the basin consists of a complexly folded series of iron formation, slates, and graywackes. One of the series of slates has a high magnetic susceptibility due to the fine-grained magnetite it contains. This formation can be detected readily. by magnetic methods and provides a marker horizon which can be easily followed. The magnetic slates are stratigraphically above the iron formation, and much of the geological interpretation of the area is based upon the magnetic anomalies they produce.

Jan 1, 1953

By A. W. Ashbrook

There are essentially three main classifications for extractants: acidic, basic, and neutral. The acidic and basic are also referred to as cationic and anionic, respectively. Some extractants are shown in Table 11-1. Acidic Extractants Acidic extractants which are of use, because of cost and/or insolubility in water, are alkylphosphoric, sulphonic, aliphatic monocarboxylic acids and naphthalene derivatives.

Jan 1, 1978

By A. J. Opinsky

ThE superior performance of nonsag tungsten wire in lamps has been ascribed to the large-grained micro-structure that can be developed in it. The orientations of these large grains have been studied several times; most published data1-' appear to be similar to those plotted in Fig. 1. These new data were obtained by X-ray back-reflection Laue technique from all of the large grains occurring in thirteen different wires that had been heated at the lowest possible temperature for the formation of large grains. Here the wire axis is plotted in terms of the principal directions of the cube. Rosi decided that the preferred orientation of the large crystals could be described by a single ideal orientation, (531), being parallel to the wire axis.' Rieck2,3 and Mannerkoski' have essentially confirmed this finding. Opinsky, Orehotsky, and Seigle argued that the data suggest that (211) is parallel to the wire axis instead of a single ideal orientation.5 This {211} contains the (531) ideal orientation and would appear to be a more general case. Ahlborn and Wassermann report that their orientation data stretch from ( 110) through (531) to (311) 8 This is part of the locus of (211). All these investigators have determined the orientations of the large grains by back-reflection Laue techniques. They have all obtained essentially similar results. On the other hand, Swalin and Geisler, who obtained their data by neutron diffraction, indicated that the preferred orientation of the large grains in doped wire is (110) .7 These findings cannot presently be reconciled with the pole density data described in the previous paragraph. Rosi1 and Rieck2 have advanced arguments about how their orientations could occur. Nevertheless, the crystallographic link between the (110) (cold-worked) fiber texture and the preferred orientation of the large grains has remained missing. This link can be provided through the concept of coincidence-type boundaries. Such boundaries separate two grains that have a certain number of common lattice sites. Coincidence relationships that result from rotations about low index directions are given by Brandon et a1 .' What is desired is a calculation of those orientations that bear a coincidence relationship with the (110) fibers of the cold-worked matrix. This situation arises in the following fashion. Heating the tungsten wire for a combination of time and temperature falling short of the formation of the nonsag structure yields a structure that is still fibrous in nature and the preferred orientation remains (110). During grain growth, the growing grain is in contact with these fibers. It is hence possible that the entire process may begin by the passage of a coincidence boundary into a (110) fiber. The calculations were carried out analytically and checked graphically. Following Brandon et a1.,8 coincidence relationships from 1 in 5 to 1 in 19 have been considered. The results of the calculations are given in Fig. 2. Of the coincidences examined, some of those occurring upon rotation about ( 110) come closest to the experimental points in Fig. 1. Nineteen of the twenty-three data points in Fig. 1 can be attributed to the ideal orientations A, B, C, and D in Fig. 2. As determined analytically, three crystals lie within 4 deg of point A, four lie within 21/2 deg of point B, eleven lie within 5 deg of point C, and one lies within 1 deg of point D-a total of nineteen. The off-lying points are near the |110| point of the triangle.

Jan 1, 1968

By Carroll F. Hardy

THE position of the coal industry has been affected by a wide variety of developments in the production and use of energy. The tempo of development and change has been increasing and the end is not in sight. Legislation is currently being proposed for commercial use of atomic power, and the employment of atomic energy in significant quantity will probably occur about the same time as the decline in production of petroleum and natural gas. But these developments are in the future and have little immediate effect on utilization and marketing of coal. While no one should try to suppress or retard the development of a new and economical source of energy, both the coal and private utility industry should be allowed to question how the nuclear power is to be used, who is to use it, and who is going to pay for it. The taxpayers have a monopoly on fissionable material and the knowledge to employ it. Any commercial use must stem from this source. It is not hard to visualize either taxpayer- subsidized private utility atomic power plants on one hand and super TVA's on the other. In view of the gains of gas and oil in the home heating field, it is interesting to compare the 1940 and 1950 census reports on the kind of fuel used for heating in occupied dwelling units. Table I shows that whereas coal provided 77 pct of the fuel for central heating (furnaces and boilers) in 1940, it was down to 45.4 pct in 1950. However, only about 1 ½ million units were lost in this 10-year period.

Jan 3, 1954

By R. A. Nadler and

Specimens of Ti-155A (Ti-5Al-1.3Fe-1.3Cr-1.2Mo), Ti-6Al-4V and Ti-4Al-3Mo-1V were hydrogenated, aged to high strength levels, and subjected to notched stress-rupture tests and tensile tests at two strain rates. Both Ti-6Al-4V and Ti-155A were relatively unaffected by hydrogen in amounts exceeding those found in commercially -produced material. Inconsistencies in the data and a relatively low initial level of ductility prevented an accurate determination of the hydrogen tolerance for aged Ti-4Al-3Mo-1V, but there was no evidence that this alloy was any more susceptible to hydrogen embrittlement than Ti-155A and Ti-6A1-4V. THE metallurgical literature has been considerably enriched in the past five years by the publication of the results of many investigations which were concerned with the effects of hydrogen on titanium and its alloys. Although it is not the authors' intention to provide a complete literature survey of this vast field, it is worthwhile to summarize briefly some of the important factors which influence the embrittling phenomenon in a - B alloys. Some of the influencing factors are those of strain rate, temperature, and composition. Hydrogen embrittlement in a - B titanium alloys is now believed to be a strain-induced phenomenon, and whether or not embrittlement occurs at high hydrogen levels depends largely upon whether sufficient time is available for hydride precipitation. This condition is fulfilled by tensile testing at very slow strain rates or by rupture testing smooth or, preferably, notched specimens over relatively long periods. Conveniently, maximum embrittlement occurs at or near room temperature. The presence B - stabilizing elements, in amounts sufficiently small to prevent an all -B or nearly all -P condition, promotes hydrogen embrittlement and this tendency is believed to be related to the amount of a - B interfacial area present. Aluminum, by increasing the solubility of hydrogen in A titanium, greatly reduces the danger of hydrogen embrittlement, while oxygen has been shown to have detrimental effects.' The preceding discussion is based on experimental work performed on annealed a - P alloys. This early work has shown that annealed Ti-6A1-4V and Ti-155A are relatively insensitive to the embrittling effects of hydrogen.' Although no work has been reported on annealed Ti-4A1-3Mo-lV, the alloy would be expected to exhibit somewhat the same insensitiv-ity as Ti-155A. In sharp contrast to the voluminous literature on annealed titanium alloys is the paucity of reported investigations on materials receiving commercial heat-treatment cycles. To date, the most notable contributions in this field have arisen from two separate investigations on Ti-3Mn-1Fe-1Cr-1V-lMo, the so-called 3Mn comple~. These investigations

Jan 1, 1961

By E. W. Johnson, M. L. Hill

Equilibrium concentrations of hydrogen in iron were measured at H2 pressures up to 136 atm and temperatures down to 145°C. Residual hydrogen was prominent near 600°C in air-melted but not in vacuum-melted iron. The diffusible hydrogen solubility is abnormally high below 390°C, confirming the hypothesis of hydrogen trapping.' It appears that the traps for hydrogen in iron form suddenly on cooling. The estimated H2 pressure in equilibrium with 5 ppm hydrogen in steel at room temperature is less than 1000 atm. It was shown previously1 that the diffusivity of hydrogen in a-Fe below 200°C is anomalously low, a behavior attributed to the presence in the metal structure of hydrogen "traps." The energy of the trapped hydrogen was computed as 4.8 kcal Per g-atom below that of the interstitially dissolved hydrogen. The strongest confirmation of the trap hypothesis should be obtainable from measurements of the hydrogen solubility at low temperatures. such measurements have been performed and are reported in this paper. The "residual hydrogen" effect1'' must be carefully controlled if valid measurements of the solubility are to be obtained, and such an effort was made in the present work. Previous data for the solubility of hydrogen in iron have been summarized by Geller and Sun.3 Their equation for the most probable solubility at 1 atm in a-Fe above 400°C is

Jan 1, 1962

By R. H. Wightman

The following paper describes current mining practices of the Riverside Cement Co. at its Crestmore plant, Riverside, California. For a number of years the Riverside Cement Co. obtained its raw materials by surface quarry operations but after these deposits were exhausted for equipment available at that time, the company started underground mining. Mine workings were begun in 1927 to 1930 for the recovery of limestone by block-caving methods. Geology The bed of limestone that is being worked is a metamorphosed and recrystallized limestone, which is generally white in color and from medium to coarsely crystalline. This bed is fissured by water courses that vary from minute cracks to large areas. The bed has also been cracked by intrusions along the footwall and hanging wall. These walls are coarse-grained, gray, quartz granodiorite. The strike of the deposit is north and south and it dips to the east at an angle of approximately 50°. The bed is approximately 1700 ft. long, 270 ft, thick at right angles to the dip at the middle of the deposit and tapers to a thickness of approximately 100 ft. at each end. Mining Methods The mine layout consists of four main levels with elevations as follows: 892 Collar of shaft. 800 Manway level used for ventilation, prospect purposes and as an entrance into the stopes. 700 Mining level where all material is extracted and on which are located the tapping grizzlies. This is the elevation from which all main cutoff stopes and undercutting work is started. 660 Haulage level where the limestone is drawn from transfer raises into the cars and is transported to the tipple by electric locomotives. 633 Level where all water is collected and which keeps the general water table below the working levels. A detailed description of the mine was given in U. S. Bureau of Mines Information Circular No. 6795, in June 1934. Current Block Development The first blocks to be caved were developed very much after the procedure followed in the copper mines of Arizona. This paper covers the ninth block to be caved. with a hard, tough rock like our limestone, it was found that some alterations in the development and control of dm, i, caving were. necessary to secure better crushing effect and provide more safety for such secondary blasting as is required. Sequence of Block Development 1. The fringes of the 800-ft. manway level are driven to confirm the diamond-drill information and serve to determine the final location and development required for the block (Fig. I).

Jan 1, 1946

By R. D. Pehlke, J. V. Gluck

The limiting activity coefficient of zinc in a "binary " solvent has been described for several dilute ternary solutions by combining literature data from recent interaction studies in the terminal regions with thermodynamic data for the central regions. Results are discussed in terms of the Alcock and Richardson random solution model. The observed behavior agrees semiquantitatively with predictions using the model. RECENT efforts in the thermodynamics of dilute ternary liquid metallic solutions have been mainly concerned with the interactions between two dilute solutes, that is, the terminal region at an apex of the composition diagram.'-' A more general case is that of the behavior of a dilute solute over the full range of a ternary system, or, more specifically, the limiting activity of solute i as projected to the k-j binary side of the i-j-k composition triangle. An implication of this is that the interaction between i and j at the k apex should connect in some way to the interaction between i and k at the j apex. A model to characterize various types of expected behavior has been discussed by Alcock and Richardson.9,10 Such behavior can range from a simple linear relation for In yi over the 1-k binary to more complex curved relations which depend on various assumptions regarding the heat of solution in the j-k binary system and the presence or absence of clustering with solute i. Quantitative data to assess these concepts have been limited primarily to the cases of nonmetallic interstitial solutes in ferrous solutions. Alcock, Richardson, and various coworkers9-13 have discussed the behavior of oxygen, sulfur, silicon, or hydrogen in dilute solution over the range of iron + metal systems; however, the only data considered by them for substitutional nonferrous metallic solutions were the results of Elliott and Chipman concerning the activity of cadmium in the Pb + Sn, Pb + Bi, and Pb + Sb systems.9 These data were limited and did not cover the terminal regions in detail. An opportunity to extend the Alcock and Richardson considerations to the dilute solution of zinc in various "binary" solvents has been afforded by combining results of several of the recent investigations of ter-minal-region interactions with previous data from the literature for the same more concentrated solutions. RESULTS AND DISCUSSION The results of the analysis are shown in Figs. 1 to 5 where the log activity coefficient, (In yZn)xzn--o, is plotted vs the composition of the "binary" solvent. In these plots the end points are the values for In yzn in the appropriate binary solution with Bi, Pb, Sn, Cd, or In at the indicated temperature—usually 550°C (823°K). For the terminal regions the slopes were drawn using the first-order interaction parameters taken from various studies reported in the literature. The data points shown in the central regions were obtained by the short extrapolation to infinite dilution of the logarithm of the activity coefficient calculated from thermodynamic studies reported in the literature for the same systems. The sources of the data are indicated on each figure. Second-order effects were not considered. Reasonably smooth curves can be drawn to connect the central region with the terminal regions for the Zn-Pb + Bi system, Fig. 1, the Zn-Pb + Zn system, Fig. 1, and the Zn-Bi + Cd and Zn-Bi + Sn systems, Fig. 2. As shown in Fig. 2, where central region data are available from two independent investigations, the agreement is quite good. The Zn-Pb + Cd system does not appear to be as well behaved as the previous four, Fig. 3; however, this type of behavior has also been

Jan 1, 1970

By R. Floyd Farris

Al thorough knowledge of the behavior of cement slurries under elevated temperatures and pressures is necessary in order to solve properly the many problems presented in deep-well cementing operations. In the earlier days of the petroleum industry the depths of wells were shallow as compared to those of today, and the subsurface temperatures and pressures were not of sufficient magnitude to affect seriously the problem of proper control of cement-slurry properties. Today, however, the search for new reserves has extended drilling to such depths that bottom-hole temperatures of more than 200°F. and bottom-hole pressures of 3000 to 5000 lb. are not uncommon. Moreover, there is every indication that within the next few years wells will be drilled to even greater depths and bottom-hole temperatures and pressures will be correspondingly higher than those with which we are concerned today. It has been realized for some time that the behavior of cement slurries at high temperatures and pressures might be very different from that at atmospheric tempera-ture-pressure conditions, but while the temperature effects have been investigated with a reasonable degree of thoroughness, the pressure effects have received little public attention. While the trend toward deeper drilling may make changes in cementing technique and the choice of cements imperative, it was the purpose of this investigation to consider factors having a bearing on the latter, only secondary consideration being ,given, for the present, to details of tech-nique and equipment for oil-field use. More specfically, the purpose of this work was to consider the effect of temperature and pressure upon the behavior of cement slurries. Although it has long been recognized that cements thicken and set rapidly with increasing temperatures, practical methods for the quantitative determination of these effects are comparatively recent developments. In 1935 Silcox and Rule1 presented such a method, describing apparatus designed to measure the consistency-time relationship of cement slurries at relatively high temperatures. The practical importance of this apparatus in furnishing useful data for the evaluation of cement slurries for cementing operations has been emphasized in various technical publications by such writers as E. L. Davis,~ I. F. Bing-ham,3 and J. E. Weiler.4 A paper describing the numerous tests now used to evaluate cements for oil wells was presented in 1939 by W. W. Robinson.= Robinson describes the Consistometer and the Thickening-Time Tester, showing similarity of data from the two devices, and points out that the purpose of each apparatus is to determine the allowable time that a cement may be pumped at a given temperature. At the present time, however, it is believed that results from the Thickening-Time Tester and the Consistometer have not given a

Jan 1, 1941

By R. Floyd Farris

Al thorough knowledge of the behavior of cement slurries under elevated temperatures and pressures is necessary in order to solve properly the many problems presented in deep-well cementing operations. In the earlier days of the petroleum industry the depths of wells were shallow as compared to those of today, and the subsurface temperatures and pressures were not of sufficient magnitude to affect seriously the problem of proper control of cement-slurry properties. Today, however, the search for new reserves has extended drilling to such depths that bottom-hole temperatures of more than 200°F. and bottom-hole pressures of 3000 to 5000 lb. are not uncommon. Moreover, there is every indication that within the next few years wells will be drilled to even greater depths and bottom-hole temperatures and pressures will be correspondingly higher than those with which we are concerned today. It has been realized for some time that the behavior of cement slurries at high temperatures and pressures might be very different from that at atmospheric tempera-ture-pressure conditions, but while the temperature effects have been investigated with a reasonable degree of thoroughness, the pressure effects have received little public attention. While the trend toward deeper drilling may make changes in cementing technique and the choice of cements imperative, it was the purpose of this investigation to consider factors having a bearing on the latter, only secondary consideration being ,given, for the present, to details of tech-nique and equipment for oil-field use. More specfically, the purpose of this work was to consider the effect of temperature and pressure upon the behavior of cement slurries. Although it has long been recognized that cements thicken and set rapidly with increasing temperatures, practical methods for the quantitative determination of these effects are comparatively recent developments. In 1935 Silcox and Rule1 presented such a method, describing apparatus designed to measure the consistency-time relationship of cement slurries at relatively high temperatures. The practical importance of this apparatus in furnishing useful data for the evaluation of cement slurries for cementing operations has been emphasized in various technical publications by such writers as E. L. Davis,~ I. F. Bing-ham,3 and J. E. Weiler.4 A paper describing the numerous tests now used to evaluate cements for oil wells was presented in 1939 by W. W. Robinson.= Robinson describes the Consistometer and the Thickening-Time Tester, showing similarity of data from the two devices, and points out that the purpose of each apparatus is to determine the allowable time that a cement may be pumped at a given temperature. At the present time, however, it is believed that results from the Thickening-Time Tester and the Consistometer have not given a

Jan 1, 1941

By Hoyt Stoddard Gale

Recent work on borate deposits near Kramer in the extreme southeast corner of Kern County, California, is of special interest because of the information it seems to give concerning the mode of origin of the borate minerals colemanite and ulexite, especially when considered in conjunction with the valuable clue to the mode of origin of colemanite in its present known deposits given in a paper by W. F. Foshag,1 of the United States National Museum. Colemanite is found in or near original deposits of ulexite, from which it is supposed to have been derived by a change in the character of the ground water or rate of its movement or both. Indications that an alteration of this sort had produced colemanite were first recognized by the writer2 in specimens collected in the Kramer district in 1920, and sent to W. T. Schaller, at U. S. Geological Survey, for identification. The identity of the two borate minerals in these specimens was suspected when collected but not at once determined, but the relations of the minerals as seen in the specimens seemed to afford a manifest clue to the origin of the deposits. Similar specimens were obtained by the writer from deposits in Death Valley soon after he had examined the deposits near Kramer. After studying the specimens submitted to him Dr. Schaller wrote as follows: " I have finally positively identified the boron minerals you sent me with your letter of Sept. 27. The 'white fibrous mineral like ulexite, is ulexite; the 'harder nodules' in the clay are colemanite, apparently formed from the ulexite as a result of leaching, with recrystallization in place—a theory that Foshag is working on." The present paper is a report on the facts observed at the depo its near Kramer, and some general observations on the geological relations noted, which, unfortunately, still form only a very incomplete record. The intimate association of deposits of colemanite and ulexite in California and Nevada with certain volcanic rocks affords a strong pre-

Jan 1, 1926

THE CHAIRMAN (A. F. Lucas, Washington, D. C.).-Mr. Matteson has stated that the drilling of certain deep wells has proved a failure because they were abandoned too soon. He advises drilling more wells around salt domes, in the hope of finding additional oil sands. I have had some experience on the domes and believe that by drilling shallow wells, one loses time and money. I have advanced the opinion -that by drilling central wells in the -most likely location of a dome, showing is certain weakness, a better result could be obtained. I have in mind one locality where Mr. Knapp drilled a well through the salt¬the only location that I know of on the Gulf Coast where oil was found underneath the salt. Mr. Knapp found a great deal of gas in it. The salt itself was impregnated with oil and gas; and my opinion is that in such instances, instead of drilling so many wells around a dome, if you will attack at a weak point to as great a depth as a drill will go, the results will he much better. At present we have instances where drills have penetrated to 7300 or 7400 ft. in depth. Why couldn't the rich companies that are operating around the Gulf Coast arrange to get some special drilling apparatus and drill with the rotary first for, say, 3000 to 4000 ft., always in the likely location, and then proceed with the cable? I think we need just such work. In Mr. Matteson's paper lie quotes from an author whose writings in the Federal Bulletin and in the Louisiana Bulletins have been quite extensive. He states that oil and asphalt have originally been found on the surface of those domes. I have been over and examined nearly all of those domes (not all of them, because many have been developed in the last few years) and found no such occurrence at the time; and in the old well-known humps or big hills, as they generally called them; I have never found either salines or asphalt or petroleum. In only' one instance it looked as though asphalt night have exuded out of the ground, and that was in the Sour Lake, but right in that neighborhood years previous to that a company had operated commercially-they had a little refinery there-and had found it so unprofitable that they pulled up stakes and quit.

Jan 4, 1918

By J. E. Burke

RECENT investigations have elucidated many of the phenomena of the grain growth process, but have also revealed some conflicting and unexplained results. Beck and his co-workers1,2,3 have shown that grain growth continues with continued heating at one temperature until the average grain size approaches the thickness of the specimen, Plotting the logarithm of the average grain diameter, D, against the logarithm of the annealing time, t, they find the straight line relationship given by the equation: [D=Ktn [11] with possible small deviations at short annealing times. K and n are constants at constant temperature. On the other hand, Walker4 finds that, in alpha brass, the rate of growth falls off more rapidly than indicated by Eq I after long annealing, so that an equilibrium grain size is approached. Burke5 showed, using Walker's data, that time and temperature for grain growth are apparently related through an activation energy, H, according to the relationship: [t, Hr i '_ III t„ = R \T, - ~) [2]] where t1 and t2 are the annealing times necessary for the average grain size to increase from Do to D at temperatures T1 and T2 and R is the gas laws constant. In the case quoted, H had the value 60,000 cal per mol. The apparent validity of this relationship, at least up to 700°C, and the approximate value of H were later confirmed by Beck.' The results obtained by Beck, Kremer, Demer and Holzworth2 for aluminum and aluminum-magnesium alloys could not be satisfied by such a relationship, since the slope of the isothermal curves increased with increasing temperature. These data indicate and Beck, Holzworth and Hu6 later demonstrated experimentally that the only apparent factor controlling the rate of grain growth at constant temperature is the grain size. While many of the phenomena have been elucidated, a reasonably quantitative explanation of the process is lacking. There exists uncertainty even as to the primary driving force for grain growth, although there is a considerable body of indirect evidence that the interfacial energy of the grain boundary is responsible.7,8,10 Making implicit use of this assumption, several authors14,15 have pointed out that grain boundaries should migrate toward their center of curvature. Harker and Parker' have advanced this concept furthest, and show that one can expect grain boundary migration to occur only when the grain faces are curved, or when they meet at non-equilibrium angles. When the face is curved toward a grain A, for example, the atoms in the surface of grain B, on the other side of the boundary, are on the average more surrounded by the atoms of their lattice than the atoms on the surface of grain A. Because of thermal motion, the atoms at the interface will sometimes be attached to grain A and

Jan 1, 1948

By H. H. Alexander

In the early part of the last century textile fabric was used for the filtration of products of combustion and lampblack was obtained by passing smoke through a series of canvas bags. Natural draft was used to draw and force the smoke through the bags. About 1850 bag filtration was used for collecting zinc oxide. Around 1876 it was introduced for collecting the fume from lead-ore hearth smelting in Missouri. Shortly afterward it was used, first at Portland, Me., and later at Canon City, Colo., for the collection and production of zinc-lead pigment in treating mixed zinc-lead sulphides. In 1890 the Globe Smelting & Refining Co., at Denver, Colo., installed a bag house containing 1,458 bags for the recovery of fume from silver-lead blast furnaces. This installation was too small to handle all of the gases and was increased to approximately 2,300 bags. In 1900 the number of bags was again increased, making a total of approximately 2,800. The usual difficulties incident to new installations were encountered, but they were gradually overcome and the bag house became accepted as standard practice for this class of smelting, As all of the bag houses built since have followed the general lines of the Globe installation, a short description may be of interest. The general construction of the Globe bag house is shown in Figs. 1, 2, and 3. The building is 149 ft. 8 in. long by 67 ft. 4 in. wide and 40 ft. 2 in. high from the basement floor to the eaves of the roof, having brick walls 26 in. thick from the foundation up to the thimble floor, from there an 18-in. wall for 16 ft. and a 13-in. wall from this point to the top, a distance of 14 ft. 2 in. Additional stiffening is given to the walls above the basement by pilasters located every 16 ft. The end-wall construction is similar to that of the side walls with the exception of the spacing of the pilasters, which is somewhat greater. The roof is made of corrugated iron laid on 1-in. boards and supported by a timber frame work spaced 16 ft. apart resting on the basement partition walls. On top is a louver running the

Jan 1, 1915

By Edward Griffith

The anthracite industry, which produces about 50 million net tons of coal annually, has been talked of as being able to last for another century; but if the water record of the past century continues into the expected century, this expectation of many years production still to come out of the remaining reserves will not be attained. The industry will be a submerged one in fact as well as in name. A recorded forecast of what has since occurred appears on page 34 of the Mine Inspectors' reports of 1897: It should also be noticed that bodies of water had accumulated in parts of abandoned mines before duplicate surveys of the same were required by law; and as a result we have today to contend with bodies of water, the exact location and position of which are not correctly known. Since that date, 47 years ago, the implications of the foregoing comment have grown enormously. This is shown in Fig. I and in the following table showing flooded and partially flooded areas that have come into existence since the early 1930's in the northern anthracite field: Number of Year Flooded Areas 1932...................... 2 1933...................... 3 1934..................... 3 1935...................... 5 1936...................... 7 1937...................... 9 1938.................... 11 1939...................... 11 1940...................... 11 1941...................... 14 1942...................... 14 1944...................... 26 Similar conditions exist in other fields in the anthracite region. In the period between 1923 and 1940, abandonment of collieries in the southern field resulted in the flooding of approximately 60 sq. miles (30 per cent) of the field. The ahandonment of collieries in this field has imposed additional expense for pumping on the collieries still operating. This condition will be aggravated by the extension of developments and cause suspension of operations if economic conditions do not justify the assumption of additional pumping costs. During the years, the region's rainfall has not altered, but the quantity going inside the mines through breakages in the surface, brought about by extraction of the coal, has increased materially, as indicated by the ratio of tons of water pumped to tons of coal produced underground for one of the large companies in the northern anthracite field: Year Ratio 1920................. 8.4:1 1925.................. 10.6:I I930.................. II.4:I 1935................. 26.2:1 1940.................. 32.7: I 1942.................. 30.3:I The data in Table I shows the total amount of water pumped and its ratio to underground production for one of the large companies in the southern anthracite field, and shows a rapidly growing serious situation. Rainfall quickly affects the workings in all the fields. In mine inspection district 7 of the southern field the rainfall in 1935 was 92,083,000,000 gal. The total water pumped was 36,274,000,000 gal. (39.4 per cent of the rainfall). The operating mines

Jan 1, 1947

By Edward Griffith

The anthracite industry, which produces about 50 million net tons of coal annually, has been talked of as being able to last for another century; but if the water record of the past century continues into the expected century, this expectation of many years production still to come out of the remaining reserves will not be attained. The industry will be a submerged one in fact as well as in name. A recorded forecast of what has since occurred appears on page 34 of the Mine Inspectors' reports of 1897: It should also be noticed that bodies of water had accumulated in parts of abandoned mines before duplicate surveys of the same were required by law; and as a result we have today to contend with bodies of water, the exact location and position of which are not correctly known. Since that date, 47 years ago, the implications of the foregoing comment have grown enormously. This is shown in Fig. I and in the following table showing flooded and partially flooded areas that have come into existence since the early 1930's in the northern anthracite field: Number of Year Flooded Areas 1932...................... 2 1933...................... 3 1934..................... 3 1935...................... 5 1936...................... 7 1937...................... 9 1938.................... 11 1939...................... 11 1940...................... 11 1941...................... 14 1942...................... 14 1944...................... 26 Similar conditions exist in other fields in the anthracite region. In the period between 1923 and 1940, abandonment of collieries in the southern field resulted in the flooding of approximately 60 sq. miles (30 per cent) of the field. The ahandonment of collieries in this field has imposed additional expense for pumping on the collieries still operating. This condition will be aggravated by the extension of developments and cause suspension of operations if economic conditions do not justify the assumption of additional pumping costs. During the years, the region's rainfall has not altered, but the quantity going inside the mines through breakages in the surface, brought about by extraction of the coal, has increased materially, as indicated by the ratio of tons of water pumped to tons of coal produced underground for one of the large companies in the northern anthracite field: Year Ratio 1920................. 8.4:1 1925.................. 10.6:I I930.................. II.4:I 1935................. 26.2:1 1940.................. 32.7: I 1942.................. 30.3:I The data in Table I shows the total amount of water pumped and its ratio to underground production for one of the large companies in the southern anthracite field, and shows a rapidly growing serious situation. Rainfall quickly affects the workings in all the fields. In mine inspection district 7 of the southern field the rainfall in 1935 was 92,083,000,000 gal. The total water pumped was 36,274,000,000 gal. (39.4 per cent of the rainfall). The operating mines

Jan 1, 1947

By Richard B. Moore

The successful commercial production of helium during the last few years has added greatly to its scientific interest. When the quantity of an element available for experimental purposes increases within a few years by 200,000 per cent., both public and scientific interest in the element are greatly stimulated. Before the war, probably, there was not more than 10 or 15 cu. ft. of helium in existence. The larger part of this was owned by Prof. Kam-merlingh Onnes, and was used by him in connection with his low-temperature work at Leiden. By experimental work during the war and immediately afterwards, the Canadians, under Prof. J. C. McLennan, produced about 60,000 cu. ft. of helium of various grades of purity. Up to Dee. 1, 1921, when the plant at Fort Worth was shut down because of lack of funds, there had been produced during the experimental work by the U. S. Government, during the war and afterwards. 2,300,000 cu ft. of helium averaging between 92 and 95 per cent. purity. After the new appropriation was made in 1922, the production plant was again started and at the time of writing was making about 15,000 cu. ft. of helium a day. Only three of the five units were being operated because of the inability to get sufficient gas to run at full capacity. The gas supply is owned by two companies and on account of a disagreement between them, it has been possible for some time to get gas from only one. It is expected that when all five units are running steadily, the daily production will be between 30,000 and 40,000 cu. ft. of gas averaging from 93 to 95 per cent. purity. All three experimental plants used during the war have been shut down. The Air Reduction plant, using the Claude system, and the Linde

Jan 1, 1923

By Richard B. Moore

The successful commercial production of helium during the last few years has added greatly to its scientific interest. When the quantity of an element available for experimental purposes increases within a few years by 200,000 per cent., both public and scientific interest in the element are greatly stimulated. Before the war, probably, there was not more than 10 or 15 cu. ft. of helium in existence. The larger part of this was owned by Prof. Kam-merlingh Onnes, and was used by him in connection with his low-temperature work at Leiden. By experimental work during the war and immediately afterwards, the Canadians, under Prof. J. C. McLennan, produced about 60,000 cu. ft. of helium of various grades of purity. Up to Dee. 1, 1921, when the plant at Fort Worth was shut down because of lack of funds, there had been produced during the experimental work by the U. S. Government, during the war and afterwards. 2,300,000 cu ft. of helium averaging between 92 and 95 per cent. purity. After the new appropriation was made in 1922, the production plant was again started and at the time of writing was making about 15,000 cu. ft. of helium a day. Only three of the five units were being operated because of the inability to get sufficient gas to run at full capacity. The gas supply is owned by two companies and on account of a disagreement between them, it has been possible for some time to get gas from only one. It is expected that when all five units are running steadily, the daily production will be between 30,000 and 40,000 cu. ft. of gas averaging from 93 to 95 per cent. purity. All three experimental plants used during the war have been shut down. The Air Reduction plant, using the Claude system, and the Linde

Jan 1, 1923