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By Franklin Moeller

Discussion of the paper of FRANKLIN MOELLER, presented at the New York meeting, February, 1916, and printed in Bulletin No. 110, February, 1916, pp. 343 to 354. K. A. PAULY, Schenectady, N. Y.-I read with interest Mr. Moeller's paper descriptive of the mechanical parts of the new electric hoist at the Granite Shaft of the North Butte Mining Co. and as the paper treats largely of the mechanical equipment I have little discussion to offer. There is, however, one question which I would like to ask and that is, why the discrepancy in hoisting cycles between the curves given in the paper read by Mr. Sykes for the American Institue of Electrical Engineers at San Francisco and those given in the paper under discussion? In Mr. Sykes' curves the acceleration period is shown to be 16 sec. for all depths from 2,000 to 4,000 ft. inclusive, while Mr. Moeller in Fig. 2 shows 25 sec. throughout the range and in Fig. 4 shows 35 sec. Mr. Moeller's curves also show the following reductions in the peak load during acceleration: Level, Feet Mr. Sykes, Horsepower Mr. Moeller, Horsepower 2,060 3,500 3,130 3,000 3,800 3,480 Fig. 2 4,000 4,100 3,800 2,250 1,595 Fig. 4 As the purchaser's specifications called for 15 or 16 sec. I would like to know whether or not any modifications have been made in the requirements since the equipment has been installed.

Jan 5, 1916

Executive JOHN R. SUMAN, Chairman PAUL D. MERICA, Vice-Chairman CHESTER A. FULTON W. M. PEIRCE H. Y. WALKER Finance H. T. HAMIL'T'ON, Chairman ERLE V. DAVELER HENRY KRUMB Admissions FELIX E. WORMSER, Chairman GEORGE D. BARRON, Vice-Chairman PHILIP KRAFT EDWARD MEAGHER CLYDE E. WILLIAMS

Jan 1, 1941

By H. B. Small

The Ottawa river, the northeastern boundary of the Province of Ontario, and the dividing line between the latter and the Province of Quebec, has long been famous for the rafts of timber floated over its waters from the depths of the forest, and other poets besides Moore, have immortalized its beauties in verse. But with the ad vent of the railway which now pierces the forest solitudes, the days of rafting were numbered ; and the boat song is now heard no more on "Ottawa's tide," or at such long intervals only, that, when heard, it seems an echo of the past. The lumber trade is fast leav ing Ottawa City, the old headquarters of the business; and such square timber as is now cut is gradually finding other outlets than shipment to Great Britain, and other channels of transportation than the Ottawa river. Skirting the northern shore of this great river runs a vast chain of hills, assuming at times the altitude of mountains. Their geological character marks them as remnants of the earliest land of this conti nent. Following the course of the St. Lawrence from the Gulf of that name to the confluence of the river with the Ottawa, the course of which latter they then pursue, the range has been styled " the Lau rentians." Rolling in long undulations, with rounded, rather than rugged or pointed summits, they leave a margin of 8 or 10 miles, dipping in a gentle slope to the water's edge, rich for agricultural use, and dotted here and there with farms and settlements. Beyond this margin bold hills stretch northerly to blue mountains, rich in iron, lead, plumbago, and other minerals. The Apatite District.—One of these minerals is apatite, or phos phate of lime, the use of which as a material for the manufacture of superphosphate as a fertilizer has become the basis of the industry bidding Fair to prove ere long one of the chief elements of Canadian trade. So rapid has been the growth of this new industry that if the lumber business were to disappear from this mineral district, its void would be filled by that which has sprung up in connection with phosphate.

Jan 1, 1893

By H. L. Overton, J. B. Lipson

The concept of sodium single-ion equivalent activity as developed by Gondouin, Tixier and Simard,' was used to determine the filtrate resistivity-activity relationships for 150 laboratory and 49 field drilling muds. With the exception of the native and phosphate high-resistivity muds and the calcium-treated muds, the filtrate resistivity-activity relationships were found to be within 20 per cent of that for pure sodium-chloride solutions. Gondouin, et al,* previously suggested a method of treating the high-resistivity muds in quantitative electrical log analysis. A new treatment is presented which uses the P-alkalinity of the filtrate as a correlating parameter in handling the calcium-treated muds in quantitative electrical log analysis. INTRODUCTION Gondouin, Tixier, and Simard in 1957 introduced new interpretive procedures for analyzing the self-potential curve of electric logging. They re-emphasized the previous work of the Schlumberger brothers, Wyllie and others, and re-defined the activity concept in terms of a number which they termed the effective resistivity. Their procedures are particuarly effective when the connate-water resistivities are less than 0.08 ohm-m or greater than 0.3 ohm-m. For gyp muds where the calcium content is known, a procedure was presented which allows calculation of the connate-water resistivity with improved accuracy. These procedures assume that one of the fluids in the system is a pure sodium-chloride solution, but they are not limited by the assumptions. For the fresh and saline connate waters, for instance, it is assumed that the drilling mud filtrate is a pure sodium-chloride solution. For the gyp mud interpretive procedure, it is assumed that the connate water is a pure sodium-chloride solution. Brown,' on the other hand, has suggested that it would be extremely fortuitous if drilling mud filtrates could all be treated electrochemically as sodium-chloride solutions, and he cites some examples where discrepancies exist. A study has been made of the deviations of sodium single-ion equivalent activities, an of drilling mud filtrates from that of pure sodium-chloride solutions. Drilling fluids in common use on the Texas and Louisiana Gulf Coast and laboratory-controlled muds were investigated. Using a cell patterned after Gondouin, et al, (Fig. I), the equivalent activities were measured. It should be remembered here that the activity measured is merely an index which uses numbers that represent the sodium single-ion equivalent activity a,., of the mud filtrate. The membrane potential developed across the cell was determined with a null-type potentiometer. The resistivities of the solutions were measured by the four-electrode method. The resistivity system was calibrated by using saturated KC1 solution as a standard. Chemical properties of the drilling fluids studied were measured with standard API-approved equipment for the particular property in question. For the activity measurements, two shale discs were chosen to serve as cationic membranes. These two discs were both 1 1/4 in. in diameter and, respectively, 1/4 and 1/8 in. in thickness. The membrane potential, Em, was determined using the shale discs as cationic selective membranes separating two standard sodium-chloride solutions of known mean activity. Then by comparing the constant Km in the following equation, with the theoretical value of — 59 mv at 75OF, the perfection of the membrane was determined. The variation of Km for the two membranes used in this experimental work, as well as one of the many unsuitable membranes, is shown in Fig. 2. The measurement of the activity of mud filtrate involves the balancing of its combined individual activities against a standard solution of known mean activity. At the point where there exists zero potential across the membrane cell, the activity effects may be assumed equal for all practical purposes. The mechanics of making a null reading of this sort requires having a large number of different mean activity solutions. A more practical method involves

By E. C. Burke, W. R. Hibbard

Plastic deformation in magnesium single crystals was studied by tensile tests at room temperature utilizing an improved preparation and testing technique. Consistent critical resolved shear stress values for basal slip were obtained. The advent of pyramidal slip at room temperature was rationalized upon the basis of grip constraints. A bend-twinning hypothesis was advanced as an explanation of mechanical twinning which occurs as a complex stress-relief mechanism. INVESTIGATIONS of the plastic deformation of magnesium have been limited to the determination of the fundamental kinetics which may be summarized as follows: 1—Twinning on the {102).l 2— Slip on the (001) plane in the [loo] direction at room temperature.' 3—Slip on the {101) or {102) plane in the [loo] direction above 225°C." 4—Critical resolved shear stresses for basal slip in tension at room temperature of 83 g per sq mm with a variation from 57 to 127 g per sq mm." Bakarian' studied the compression of thin wafers of magnesium single crystals and classified the components of the deformation mechanisms as follows: 1—The Basal field: (001) at an angle of less than 20" to the compression surface. Fracture along {101} or slip on (001) followed by {101} fracture. 2—The prism field: (001) at an angle greater than 60" to the compression surface. Twinning on the {102) generally occurring during the early stages of loading, basal slip in the areas of original orientation and (001) slip within twins. 3—The central field: (001) at angles greater than 20" but less than 60" to the compression surface. Slip on the (001). 4—The critical resolved shearing stress for {101} slip above 225°C was 400 g per sq mm. Observations of mechanical twins in hexagonal close-packed metals have been summarized by numerous investigatorsb-' emphasizing a lateral or rotational atomic adjustment, in addition to the pure twinning shear, and the importance of reorienting the basal plane to a position more favorable for continued slip, rather than the resulting small dimensional changes. Criterion for the operative twinning planes has not been clearly established. Schmid and Boas hurmised that an energy condition related to the atom movements is the determining factor. MillerQ bserved that twinning stresses in zinc crystals decreased as the amount of prior deformation increased. Preparation of Specimens Magnesium single crystals % in. in diam x 8 in. long were grown from the melt under an argon atmosphere in a gradient furnace similar to that described by Jillson." Magnesium containing 0.018

Jan 1, 1953

By P. M. Aziz, I. Markson, C. S. Barrett

The abnormal after-effect in twisted wires that occurs when untwisting is interrupted by etching con be brought under control and used to study the mechanical properties of thin surface films and how they are effected by reagents and heat treatment. Results are given of studies of oxide films on high purity aluminum. IF a wire is subjected to plastic deformation by torsion and then released, it untwists in the normal after-effect, but under certain circumstances the untwisting is abruptly lessened or reversed by the application of an etchant to the wire.1,2 This abnormal after-effect may occur, for example, if there is a coherent oxide film on the surface of the wire which is removed by the etchant. Following a suggestion of A. H. Cottrell that predicted this effect, it is attributed to dislocations that had piled up beneath the oxide layer and represents the rapid release of residual stresses caused by these dislocations. When the layer is removed, the stress relief may be by escape of piled-up dislocations from the metal, or by an activation of latent sources of dislocations located at the surface, together with rebalancing of elastic stresses to compensate for the loss of stressed material, as in a residual stress analysis determination, these mechanisms acting singly or in combination.' The slower the attack of the reagent, the more gradual is the stress relief and the smaller the change in strain rate when the reagent is applied. A study has been made of the factors that influence the magnitude of the normal and abnormal after-effects with the object of developing techniques suitable for a quantitative investigation of the influence of various surface films on dislocations in wires, and of the rate and extent of the attack on the films by different reagents. It was found that reasonable sensitivity and reproducibility could be achieved if a suitable choice of variables was made and if these variables were held constant through a series of experiments. The method was then applied to a study of oxide films produced and treated in different ways on the surface of high purity aluminum wires, and to a study of the damage to these films caused by various reagents. Experimental Procedure The material used throughout this work was prepared from 99.9968 pct Al. This high purity aluminum was melted, cast into 1/2 in. diameter ingots, and then swaged and drawn without intermediate annealing to 0.040 in. diameter wire. A sketch of the apparatus employed for twisting is shown in Fig. 1. The test wires were mounted into the apparatus by cementing one end of the wire to the beaker and the other to the tube with laboratory wax of high melting point. The length of the wire between the waxed joints was 4.2 & 0.2 cm. Extreme care was taken during mounting to avoid cold-working the wire. The wire was twisted through 335" in 2 to 4 sec by rotating the pinion on the gear box until the vertical post on the rotating table, which was initially touching the horizontal stop, was arrested by the stop. All the tests were conducted with apparatus and reagents at the same temperature (about 25°C). In all tests, except those where the duration of the initial torque was investigated, the torque was applied for a period of 2 min. At the end of this time the table was rotated back a few degrees away from contact with the stop and the wire allowed to untwist. The after-effects were measured by reflecting a beam of light from the mirror shown on the apparatus. After the wire had untwisted for 6 min, a reagent was carefully poured into the beaker and thereby applied to the surface of the wire.. In some tests the liquid in the beaker was removed after a few minutes and replaced by an-

Jan 1, 1954

By E. V. Kleber, V. F. Novy, R. C. Vickery

The constitutional diagram has been determined for the system gadolinium-nickel. Nine intermetallic compounds have been found at compositions corresponding to the following gadolinium-nickel ratios: 3:1, 3:2, 1:1, 1:2, 1:3, 2:7, 1:4, 1:5, 2:17. The GdNi and GdNi5 compounds have congruent melting points of 1300' and 1500°C, respectively while the remaining compounds melt in-congruently. Eutectics exist at 15 wt pct Ni, 31 1/2 wt pct Ni and 87 wt pct Ni with melting points of 6703 8803 and 1220°C, respectively. IN a continuing investigation of the properties of rare earth alloys, a study has been made of the gadolinium-nickel system. Previous work encompassed the iron containing alloys and a subsequent paper will deal with the constitution of the gadolinium-cobalt system. Vogel,1 examined alloys of nickel with lanthanum and cerium. R3Ni, RNi, RNi2, RNi3, RNi4, and RNi5 compounds were found. Endter and Klemm,2 Fulling et al.3 Heumann,4 and Nowotny5 found the 1:2 compositions of this series to exist in a C-15 (face-centered cubic) structure, and the 1:5 compositions in a hexagonal system. Jepson and Duwez6 more recently examined these 1:2 and 1:5 compositions and generally confirmed earlier data while Wernick and Geller7 most recently have given additional data on the GdNi5 compound. Comparisons with our results will be made in the appropriate section of this report. EXPERIMENTAL Methods of alloy preparation, annealing procedures, and experimental techniques have been given in our earlier paper.8 Chemical analyses of the alloy samples were made by dissolving the specimen in nitric acid, precipitating the gadolinium as hydroxide and the nickel with dimethylglyoxime. Both precipitates were ignited to oxide and weighed. RESULTS Microstructure— Metallography of alloy specimens in this series has been conducted on both arc-melted and annealed materials. Etchants used have been 5 pct nital with approximately 10 pct distilled water added, for high gadolinium samples; Carapella's ferric chloride solution for intermediate compositions; and Marble's (copper sulfate) reagent for high nickel content alloys. Because of difficulties encountered in the grinding and polishing of specimens containing 40 to 75 wt pct Ni, no photomicrographs were made of such specimens. The microstructure of an arc-melted 5.3 wt pct Ni alloy is shown in Fig. 1. Light etching primary grains of gadolinium are embedded in an eutectic matrix. The microstructure of an alloy of 9.55 wt pct Ni alloy, Fig. 2, annealed 50 hr at 700°C, consists almost entirely of the intermetallic compound Gd3Ni. The structure of an arc metal alloy of approximately 19 pct Ni, Fig. 3, consists of grains of the compound GdNi embedded in the Gd3Ni2-Gd3Ni eutectic. The arc-cast structure of the 38.7 wt pct Ni alloy is shown in Fig. 4. Large primary grains of a compound rest in a matrix structure of coarse GdNi-GdNiz eutectic. Because of the occurrence of several peritectic compounds in the central region of the diagram, identification of the primary structure in this alloy is not certain. As has been indicated above, microstructures of alloy specimens containing between ca 40 and 75 wt pct Ni have not been photographed. These specimens were highly brittle, and macro- and micro-cracking were impossible to control in the grinding and polishing procedures. Prolonged annealing did not alleviate this condition. Visual observations in small specimens did, however, provide evidence for a multiplicity of phases and peritectic dissociations of compounds although rationalization of structures was not possible.

Jan 1, 1962

By Allan T. Gwathmey, J. Bruce Wagner, Kenneth R. Lawless

Between 250°and 550°C in oxygen pressures of 10 to 760 mm Hg, the relative oxide thicknesses formed per unit time on the (100), (111), (110), and (320), decreased in this order. The predominant oxide orientation was (001)Fe3O4 and [110] Fe304 A small amount of a-Fe2O3 which exhibited a fiber pattern was observed in all oxides except those formed at 250°c in low oxygen pressures. IN order to understand the properties and behavior of thin films, particularly their role in oxidation reactions, there is needed more experimental information on their structure, composition, and kinetics of formation on clean surfaces of known geometry. The present study was undertaken to obtain such information for thin oxide films formed on single crystals of a body centered cubic metal, iron. Crystals in the form of spheres were used in order to expose all possible crystal planes to the reactant gases simultaneously. Using this procedure the relative rates of oxidation of all planes could be estimated, and those exhibiting, maximum or minimum oxidation rates could be selected for a more intensive study of composition and expitaxy. Since the three types of information were obtained from the same experiment using a single crystal substrate, any differences between rate, composition, and expitaxy on the several planes may be attributed to the influence of the substrate structure. EXPERIMENTAL The starting material for this study was Armco iron rods, 6 in. long and 3/8 or 1/2 in. in diam. The analysis was reported to be 99.8 pct Fe, with major impurities listed as carbon 0.018 pct, manganese 0.027 pct, phosphorous 0.005 pct, sulfur 0.029 pct, silicon 0.005 pct, and copper 0.11 pct. These rods were cleaned with ether and heated in an atmosphere of moist hydrogen at 950°C for three days. The purpose of this treatment was to decarburize the iron and to provide a consistent, uniform grain size for the growth of single crystals. Crystals in the form of rods, up to 1/2 in. in diam and 2 in. long, were prepared by a method similar to that reported by Leidheiser and Buck.2 Spherical crystals, 3/8 and 1/2 in. in diam and having a handle about 1/4 in. in diam by 112 in. long, were machined from the single-crystal rods. After machining, each crystal was etched in aqueous nitric acid to remove the cold-worked metal at the surface. Before each experiment, the crystal was polished mechanically with metallographic papers through number 4/0, and electropolished in a perchloric acid-acetic anhydride mixture by the method of Jacquet and Rocquet.3 The crystal was washed in running distilled water for at least 5 min. The excess water was blotted with a soft paper tissue, and the crystal was placed in an all-glass reaction vessel (See Fig. 1). The crystal was heated at 550°C in hydrogen for at least 8 hr prior to the oxidation in order to reduce any surface oxides and to help relieve any stresses in the metal. For the structure and composition studies, flat faces were cut parallel to (loo), (111), and (110) planes on the iron crystal spheres. The orientation of these faces was checked by a back-reflection X-ray diffraction technique. The faces were within 2 deg of the desired orientation. The flat faces were treated as described above except that prior to electropolishing they were given an additional polish on metallographic felt saturated with twenty-minute levigated alumina. After the crystal was heated in hydrogen for at least 8 hr, the temperature was adjusted to the desired value, and the hydrogen was evacuated. Commercial oxygen which had been purified by successively passing through tubes containing magnesium perchlorate, Ascarite and magnesium perchlorate was admitted to the desired pressure as measured by a mercury manometer. A resistance-wound furnace surrounded the oxidation chamber, and a temperature controller maintained the temperature within ±3°C. The furnace was provided with a small window for observing the crystal. The changes in thickness of the oxide films were followed by observing the interference colors. The oxidation was allowed to proceed until the desired oxide thickness was attained on a given crystal plane. The experiment was terminated by evacuating the oxidation

Jan 1, 1962

AARONS, J. BOYD; Major. AGNEW, FRANK VANS. ALLEN, HERMAN H., Private, D Co., 8th Reserve Engineers. AMBLER, HARRY A., Second Training Camp,, Ft. Sheridan, Ill. BAINS, THOMAS M., JR., Major, Engineer Officers' Reserve Corps. BANKS, H. R., Lieutenant, Canadian Engineers, B. E. F. BARBOUR, PERCY E., Deputy' Supt. (Captain), New York State Troopers; Captain, 22d Regiment, N. Y. N. G. BARLING, H. B., 1st Lieutenant, Engineer Officers' Reserve Corps. BARRETT, LESLIE P., Lieutenant, A. E. F., France. (Unattached.) BENSEL, J. A., Major, Engineers' Reserve Corps. BIGELOW, BRAXTON, Royal Engineers, B. E. F. BLOOMFIELD, E. C., Lieutenant. BORROW, F. K. BOWLES, MARTIN F., 2d Lieutenant of Infantry, Camp Funston, Kans.

Jan 11, 1917

By Frank G. Breyer

C ONDITIONS have not been favorable for new developments in any line. It has been a period, how- ever in which recent developments have been subjected to the severest tests. Those which have been able to hold their own in the severe competition of 1932 must be considered fully proved commercial processes. The continuous vertical-muffle retort plant at Palmer- ton is reported to have been in operation at practically full capacity throughout the year. The high quality of metal produced and the low operating costs are factors which have kept this plant running when many of the older furnaces were shut down. The plant at Meadow- brook, W. Va., is also reported to have been in steady operation throughout the year. Average retort life is said to be better than two years with about three-quarters of the original retorts still in operation after 2 ½ years.

Jan 1, 1933

By Alfred E. Hunt, Geo. H. Clapp

The great advantage to he gained by a careful inspection of all materials used in construction, in regard to safety and permanency, and to accuracy of workmanship, has been longer recognized in Great Britain and on the Continent than in America. This is probably owing to the way in which great enterprises have been " rushed" in the United States. Time and cheap first cost, in too many instances, have been considered of more importance than absolute safety and durability; the structures being afterwards strengthened if this was found necessary. This has been most noticeable in railroads built through " new " country, where the object in view has been to reach the terminal point and get to work. These " loose " methods are now being very largely done away with, and a large proportion of the structures lately built are not only carefully inspected during the process of

Jan 1, 1891

By L. K. Nemeth, H. T. Kennedy

The investigation presented in this paper was performd to develop a relationship between the dewpoint pressure of a hydrocarbon reservoir fluid and its composition, temperature and characteristics of the heptanes-plus fraction. This is part of an over-all program to develop correlations for the essential properties of reservoir fluids with the composition, temperature and pressure. In all, 579 dewpoint pressures, determined experimentally on 480 different condensate systems along with their compositions and temperatures, were obtained from the literature and from previously unpublished sources. Compositions were expressed in terms of mol fractions of methane through heptanes-plus, nitrogen, carbon dioxide and hydrogen sulfide, and the molecular weight and specific gravity of the heptanes-plus fraction. Distribution of the samples assured a good representation of most of the major oil-producing areas in the world. A multiple regression analysis program written for the IBhl 7094 digital computer was used to compare numerous equations and to calculate their coefficients. The final equation containing 11 coefficients resulted in an average absolute deviation of 7.4 percent for all the samples. Segregation of data on the basis of one or more variables did not materially improve the results. The correlation developed is useful in predicting the dewpoint pressure of condensate reservoir fluids from variables normally measured in the laboratory. INTRODUCTION In any discussion of the dewpoint of hydrocarbon mixtures, it should be noted that there are two kinds of dewpoints which must be distinguished. The first type, or normal dewpoint, usually occurs at low pressures as dry gas is compressed to the point where liquid first forms. The second type, sometimes called the retrograde dewpoint, occurs when a gas mixture containing heavy hydrocarbons in solution is depressured until a liquid is formed. The first type, as applied to condensate mixtures, would normally be below atmospheric pressure and would be of no interest in reservoir performance. The second type is of great significance in interpreting reservoir behavior and is the property referred to throughout this paper. Laboratory measurement of dewpoints is laborious, expensive and subject to many errors, and it is desirable to find a reasonably accurate method to predict dewpoint pressures from the composition and other readily available properties normally measured on the fluids. A possible method of calculating dewpoint pressures would be to employ a set of equilibrium ratios (K-values). 1 However, the K-values themselves depend on composition as well as temperature and pressure; presently their use adds nothing to the accuracy of predicting dewpoints. If future correlations provide a significantly better method of estimating K-values for heavy hydrocarbons, they may be of greater use. REVIEW OF LITERATURE In 1944, Olds, Sage and Lacey 2 studied the behavior of fluids from the Paloma field. Properties of seven mixtures were studied at temperatures ranging from 100 to 250 F and at pressures up to 5,000 psia. From the information obtained, the influence of composition and temperature upon the dewpoint was determined. It was found that removal of the intermediate molecular weight components from the mixture resulted in considerable increases in the dewpoint pressures. Results indicated that the effect of changes in temperature was relatively minor when compared with the effect of modifying the mixture by removing the intermediate components. Thus, removal of propane and butanes resulted in an increase in dewpoint pressure more than 10 times greater than a change in temperature from 100 to 250 F. The authors stated that althouah

By High Archbald

It is possible to construct a simple diagram of the earnings, or the production, of the men employed at a coal mine that will show not only if the conditions tend toward contentment among the men, but if the operating distribution of the work is correct. As earnings are the greatest cause of discontent, even exceeding all the other causes, if contentment exists in the matter of earnings, the likelihood of other discontents flaring up is greatly lessened. The basis of such a diagram would be the Gaussian curve of the normal variation in human ability. Such a curve has long been recognized. H. L. Moore,' in discussing the quantitative relation between wages and ability says: "It has been pointed out that industrial efficiency is dependent upon physical, mental, and moral qualities, and these qualities . . . there is good reason for regarding as being distributed according to the Gaussian law.

Jan 1, 1925

By Hugh Archbald

IT is possible to construct a simple diagram of the earnings, or the production, of the men employed at a coal mine that will show not only if the conditions tend toward contentment among the men, but if the operating distribution of the work is correct. As earnings are the greatest cause of discontent, even exceeding all the other causes, if contentment exists in the matter of earnings, the likelihood of other discontents flaring up is greatly lessened. The basis of such a diagram would be the Gaussian curve of the normal variation in human ability. Such a curve has long been recog-nized. H. L. Moore,1 in discussing the quantitative relation between wages and ability says: "It has been pointed out that industrial efficiency is dependent upon physical, mental, and moral qualities, and these qualities . . . there is good reason for regarding as being distributed according to the Gaussian law..

Jan 7, 1924

By W. I. Garms, J. L. Stevens

Because of the many conflicting opinions regarding the functioning of the ball load and the characteristics of ball wear in ball-mill grinding, the following résumé of reports covering recent tests conducted at the Hayden plant of the Kennecott Copper Corporation is submitted with the view of pointing out certain salient features that should throw additional light on the subject. Mills Used Cylindrical drum mills with trunnion feed and discharge were used. The discharge trunnion was 13½ in. in diameter. Dimensions inside the lining were 6 ft. 6 in. in diameter and 9 ft. 6 in. long. The mills were Britannia-lined and nine lifter bars projected 2 in. from the lining. The mill speed was 162/3 r.p.m. Feed to the mill was 9 per cent on 10-mesh, 85 per cent on 100-mesh, 77 per cent solids. New balls measured 2 in. in diameter and the approximate weight of the ball load was 40,000 pounds. Initial Test During a test that was being conducted to determine the relative economic value of standard cast balls vs. forged steel balls in the local 'grinding operation, certain observations were made in regard to the functioning of the various ball sizes and the characteristics of ball wear, which warranted a supplementary test for the purpose of confirming such observations. For the initial test, the necessity for developing a graduated load of the new forged balls before the test could be started was realized, but the time required to obtain a graduated load and the functioning of the various ball sizes was not clear. No advantage could be seen for starting out with a full load of forged balls, as this initial load, at the least, would have to be completely ground out and replaced by daily additions of balls before the graduation could be complete and a normal static condition of ball sizes reached. For a considerable period prior to exhaustion of this initial charge there would be an unusual quantity of worn balls of a certain size, which would not be typical of a normal charge and could influence the characteristics and functioning of the entire load. Therefore, it was decided to start by daily addition of the forged balls to a mill that contained a normal operating load of cast balls. After 88 days of operation the mill was shut down for inspection. By that time the load consisted of a mass of forged balls functioning around a large core of the residual material of the former cast-ball load. This core of cast slugs, locally referred to as "the kidney," was well defined from the forged-ball load.

Jan 1, 1947

By W. I. Garms, J. L. Stevens

Because of the many conflicting opinions regarding the functioning of the ball load and the characteristics of ball wear in ball-mill grinding, the following résumé of reports covering recent tests conducted at the Hayden plant of the Kennecott Copper Corporation is submitted with the view of pointing out certain salient features that should throw additional light on the subject. Mills Used Cylindrical drum mills with trunnion feed and discharge were used. The discharge trunnion was 13½ in. in diameter. Dimensions inside the lining were 6 ft. 6 in. in diameter and 9 ft. 6 in. long. The mills were Britannia-lined and nine lifter bars projected 2 in. from the lining. The mill speed was 162/3 r.p.m. Feed to the mill was 9 per cent on 10-mesh, 85 per cent on 100-mesh, 77 per cent solids. New balls measured 2 in. in diameter and the approximate weight of the ball load was 40,000 pounds. Initial Test During a test that was being conducted to determine the relative economic value of standard cast balls vs. forged steel balls in the local 'grinding operation, certain observations were made in regard to the functioning of the various ball sizes and the characteristics of ball wear, which warranted a supplementary test for the purpose of confirming such observations. For the initial test, the necessity for developing a graduated load of the new forged balls before the test could be started was realized, but the time required to obtain a graduated load and the functioning of the various ball sizes was not clear. No advantage could be seen for starting out with a full load of forged balls, as this initial load, at the least, would have to be completely ground out and replaced by daily additions of balls before the graduation could be complete and a normal static condition of ball sizes reached. For a considerable period prior to exhaustion of this initial charge there would be an unusual quantity of worn balls of a certain size, which would not be typical of a normal charge and could influence the characteristics and functioning of the entire load. Therefore, it was decided to start by daily addition of the forged balls to a mill that contained a normal operating load of cast balls. After 88 days of operation the mill was shut down for inspection. By that time the load consisted of a mass of forged balls functioning around a large core of the residual material of the former cast-ball load. This core of cast slugs, locally referred to as "the kidney," was well defined from the forged-ball load.

Jan 1, 1947

By J. F. Poland

Location of Basins and Geologic Features of Occurrence: The major ground-water resources of California occur and are stored in the many large alluvium-filled valleys of the state. The deposits of Quaternary age which hold the ground water commonly are called valley fill. Meinzerl has discussed the characteristic features of this fill and showed that for western United States its distribution is concentrated chiefly in western Utah, Nevada, central Oregon, California, southern Arizona, and central New Mexico (see fig. 1). For California the principal ground-water basins are shown on fig. 2. Except for the Mojave Desert and the "Basin and Range" Valleys (fig. 2, Nos. 23 and 23A), which are not shown individually, the basins outlined on fig. 2 contain all the large reservoirs in valley fill within the state. The Sacramento and San Joaquin Valleys (fig. 2) together comprise the Great Central Valley of California, which has an area of about 18,000 square miles. The Sacramento Valley contains about 5000 square miles of valley lands, approxi- mately equal to the area of Connecticut; the San Joaquin Valley embraces about 13,000 square miles, equivalent to the areas of Massachusetts and Connecticut combined. Both the area and the ground-water use in the Central Valley is far greater than for all the other shaded alluvial basins of fig. 2 added together. Except for the Sacramento Valley, all the major ground-water basins of the state are south of Sacramento. The valley fill in these ground-water basins has been transported by streams and most of it has been laid down in alluvial fans, producing the typical alluvial-fan structure of aquifers radiating as tongues from a prismatic pile of coarse, permeable debris at the canyon mouths; these aquifers are encased down slope by poorly sorted materials consisting of a clayey matrix with imbedded pebbles and boulders, interbedded with flood-plain silt. In the deeper inland structural valleys, the alluvial deposits interfinger at depth in the valley bottoms with horizontally bedded lacustrine sand, silt, and clay. The San Joaquin Valley is a good example. In the coastal valleys exposed to the sea, such as the Los Angeles coastal plain, the alluvial fans pass coastward into lagoonal and thence to shallow marine deposits. In all these basins, the gravel is coarsest and most permeable near the apexes of the fans, but tongues or lenses of clean gravel and sand may extend for many miles down the fan. Thus, these water-bearing structures are in a position to absorb stream flow near the canyon mouths and to transmit it through the buried radiating conduits.

Jan 1, 1951

By J. F. Poland

Location of Basins and Geologic Features of Occurrence: The major ground-water resources of California occur and are stored in the many large alluvium-filled valleys of the state. The deposits of Quaternary age which hold the ground water commonly are called valley fill. Meinzerl has discussed the characteristic features of this fill and showed that for western United States its distribution is concentrated chiefly in western Utah, Nevada, central Oregon, California, southern Arizona, and central New Mexico (see fig. 1). For California the principal ground-water basins are shown on fig. 2. Except for the Mojave Desert and the "Basin and Range" Valleys (fig. 2, Nos. 23 and 23A), which are not shown individually, the basins outlined on fig. 2 contain all the large reservoirs in valley fill within the state. The Sacramento and San Joaquin Valleys (fig. 2) together comprise the Great Central Valley of California, which has an area of about 18,000 square miles. The Sacramento Valley contains about 5000 square miles of valley lands, approxi- mately equal to the area of Connecticut; the San Joaquin Valley embraces about 13,000 square miles, equivalent to the areas of Massachusetts and Connecticut combined. Both the area and the ground-water use in the Central Valley is far greater than for all the other shaded alluvial basins of fig. 2 added together. Except for the Sacramento Valley, all the major ground-water basins of the state are south of Sacramento. The valley fill in these ground-water basins has been transported by streams and most of it has been laid down in alluvial fans, producing the typical alluvial-fan structure of aquifers radiating as tongues from a prismatic pile of coarse, permeable debris at the canyon mouths; these aquifers are encased down slope by poorly sorted materials consisting of a clayey matrix with imbedded pebbles and boulders, interbedded with flood-plain silt. In the deeper inland structural valleys, the alluvial deposits interfinger at depth in the valley bottoms with horizontally bedded lacustrine sand, silt, and clay. The San Joaquin Valley is a good example. In the coastal valleys exposed to the sea, such as the Los Angeles coastal plain, the alluvial fans pass coastward into lagoonal and thence to shallow marine deposits. In all these basins, the gravel is coarsest and most permeable near the apexes of the fans, but tongues or lenses of clean gravel and sand may extend for many miles down the fan. Thus, these water-bearing structures are in a position to absorb stream flow near the canyon mouths and to transmit it through the buried radiating conduits.

Jan 1, 1951

By J. E. Berry

AII evaluation is made of the acoustic velocity log for measurement of formation porosity. Plots of field-observer1 velocities vs core-measured porosities of sandstones and limestotnes with inter intergranular porosity show that the velocity log gives a useful measure of porotity, in agreement with published data. A new method of plotting electrical and velocity log data makes it easier to recognize hydrocarbon-water coritnct~ from log darn and to make serni-quantitative estinlates of hydrocarbon saturation. Two examples of this interpretation technique are given. This paper also discusses the various factors that affect acoustic velocity and shows how corrections can be made for some of these factors. INTRODUCTION Although the continuous velocity log was developed primarily as an aid to seismic interpretation, it is finding widespread use for measurement of porosity. The purpose of this paper is to evaluate this use of the log. Results are presented for the velocity-porosity relationship in many sandstones and one limestone. Practical applications of porosity values derived from the velocity log to improve interpretation of electrical surveys are presented. Various parameters which affect velocity in porous media are considered. Porosity, composition, cementa-tion, pressure difference (overburden pressure minus fluid pressure), fluid saturation, and wellability are discussed. Some of the ideas are opinions based on general considerations of well logging problems while others are supported by published data and our own observations. Major conclusions from these studies arc given in the body of the paper and detailed discussions of some of the various factors affecting porosity are given in the Appendix. POROSITY Sandstones The primary factor affecting the velocity of sound in porous media is porosity. Wyllie, et al,1 have reported a time average equation for the relationship between velocity and porosity.* This has found considerable acceptance in the industry. Other relationships between velocity and porosity have been proposed, none of which are entirely satisfactory. It is doubtful that any one relationship will completely describe all situations. We have tried an empirical relationship based on correlating log velocities with core-measured porosities. Measured porosities were averaged over a depth interval equal to the spacing used in recording the velocity logs. The depth range for the information used was from 2,000 to 12,000 ft. Velocity measurements were normalized for the effects of depth and overburden pressure. A detailed discussion of the basis for this normalization is given in the Appendix. The change is usually insignificant and when working with individual formations it can be neglected. All velocity measurements were normalized to a depth of 10,000 ft. The velocity-porosity data for sandstones in Fig. 1 came from 20 wells scattered throughout the Mid-Continent and Gulf Coast areas. The scatter of the data points is attributed to three causes: 1. There is no theoretical basis for expecting an exact velocity vs porosity relationship and it is not possible to correct precisely for the effects of such factors as impurities, grain shape, manner of cementation, etc. Some of these factors are discussed in the Appendix. 2. Porosities measured by core analysis are not necessarily representative of what the velocity log "sees". 3. Inaccuracies appear in the velocity log reading. This is particularly true of velocities from one-receiver logging tools.*" A linear-time curve (time-average equation) is plotted in Fig. 1 along with the best straight line through the points. Velocities used for the linear-time curves were 19,500 ft/sec for the matrix velocity (zero porosity) and 5,500 ft/sec for fluid velocity. For clean sandstones with velocities greater than 10,000 ft/sec, there is little difference between the velocity-porosity and the time-porosity curves. Both curves are well within the scatter of data points. The data points in Fig. 1 were restricted primarily to clean sandstones, using the SP and/or gamma-ray logs as clues to the lithology. Where a lithologic de-

By F. R. Scauzillo

Equilibrium data which should be useful in the design and/or evaluation of glycol dehydration units were prepared from an analysis of various published data and the correlation of these data by the use of the thermo-dynamic equilibrium ratio. The equilibrium ratios of water are used to solve the glycol absorber problem; such solutions are necessary to define the number of trays and the glycol circulation rate needed to meet drying requirements. Activity coefficients were obtained which relate directly to the equilibrium ratios of water in the water-TEG-natural gas system. These activity coefficients have been used to calculate the equilibrium dew points for aqueous TEG concentrations of 60 to 99.9 weight per cent for the temperature range of 40° to 120° F. They also provide a means of calculating equilibrium ratios for water in the water-TEG-natural gas system; this applies to any desired TEG concentration and to the temperature range from 40° to 120°F. INTRODUCTION During the last several years, the drying of natural gas with aqueous triethylene-glycol (TEG) solutions has become very prominent. Most users of TEG as a drying agent have been satisfied with the performance of TEG solutions at the conditions used; however, there always has been some discussion of the drying ability of TEG solutions at conditions not commonly encountered such as temperatures below 50° or 60°F, but more particularly temperatures above 100°F, and pressures above 1,000 psia. Today, when higher wellhead temperatures such as 120°F are more commonly encountered many are skeptical of TEG's ability to dry sufficiently well to provide dew points around 32°F, which is generally the maximum tolerable when attempting to dry a gas to contract specifications of 7 Ib/MMscf. These views probably have evolved to some extent from the days when suppliers would not guarantee dew-point depressions in excess of 65° to 75 °OF. Also, the feelings about TEG drying may have arisen from the lack of information about the equilibrium relation of water in the drying operations. Porter and Reid' have reported equilibrium data for a 95 per cent TEG solution, while Townsend2 reported equilibrium data for 95, 98 and 100 per cent TEG solutions. Townsend also presented a calculational method which obtains activity coefficients in the liquid phase and, subsequently, the equilibrium water content of a saturated gas over glycol from published3 atmospheric dew points. Wise, Puck and Failey' presented activity data for the water-TEG system at atmospheric pressure. In the past, the equilibrium ratios published for water in a 95 per cent by weight aqueous TEG solution have been used indiscriminately by many for all concentrations of TEG encountered in gas drying operations. Since essentially all such gas operations require the use of more concentrated TEG solutions, a study was undertaken to correlate the existing equilibrium data for aqueous TEG and gas systems and to provide some means of calculating the equilibrium ratio of water in the natural gas-water-TEG system where TEG concentrations were other than 95 per cent. The data presented herein consider only the equilibrium drying ability of the TEG solutions and do not consider the effect of temperature and pressure on the tray eficiency of contactors. In other words, this paper is concerned primarily with the development of the equilibrium relationship between water in the dried natural gas and the water in the lean TEG entering the top tray of the absorber. BASIC EQUILIBRIUM RELATIONS A relationship which relates the K value of water in the natural gas-water-TEG system to the vapor pressure of water at the system temperature, the total pressure of the system and the activities of the liquid and gas phases has been evaluated. It is well known that, for any component of a mixture at equilibrium between a gas phase and a liquid phase,