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By Frank W. Harris

THE strength of hard drawn copper wire is a question of considerable importance to both manufacturer and consumer. Unlike steel and alloy wires, in which strength is governed by both chemical and physical considerations, the high conductivity required for copper wire in the electrical industry generally precludes the possibility of obtaining tensile strength through the use of alloys. Consequently, this strength is largely a matter of the physical structure, and all factors known to affect this structure, such as rolling temperature, die contours, lubricants, drawing speeds, etc., are matters of prime importance. The experiments described here have been carried out during the past year at the Baltimore plant of the American Smelting & Refining Co., in connection with a general investigation of some of the questions mentioned above, with the object of studying the physical structure of hard drawn copper wire and the influence of certain factors on that structure. The work has been of an exploratory nature, rather than comprehensive, but it was thought that the results might prove of sufficient general interest to warrant their publication. The bulk of the hard drawn copper wire used in places where strength is an important factor is manufactured to strict specification, based usually in the United States on that of the American Society for Testing Materials (B-1-23). This specification calls for almost as high a value of tensile strength, consistent with elongation, as it is possible practically to obtain, and only physically perfect material can be relied on to meet such a specification. Obvious defects, such as laminations produced through fins in the original rods or brittleness due to overdrawing, are usually recognized and need only passing reference. Laminations can be detected by twisting and untwisting the wire several times; they will show up on the surface in the form of fins. Fig. 1 shows a very bad example of this defect. The wire may be perfectly smooth before twisting but when such laminations are present they will readily show up under this treatment. This trouble is caused by similar defects in the original rod produced by overfills in rolling. Fig. 2 shows the cross-section of the rod from which the wire in Fig. 1 was drawn.

Jan 1, 1928

By John W. Roberts

The Federal income tax law permits as a deduction in determining net income "in the case of mines,... a reasonable allowance for depletion and for depreciation of improvements, according to the peculiar conditions in each case, based upon cost, including cost of development not otherwise deducted: Provided, that in the case of such properties acquired prior to Mar. 1, 1913, the fair market value of the property (or the taxpayer's interest therein) on that date shall be taken in lieu of cost up to that date." The law provides for a reasonable allowance but the regulations provide for a definite method of computation that possesses more the virtue of simplicity than that of reasonableness. Article 210 of Regulations 45 reads: "When the cost or value as of Mar. 1, 1913, or within 30 days after the date of discovery of the property shall have been determined, and the number of mineral units in the property as of the date of acquisition or valuation shall have been estimated, the division of the former amount by the latter figure will give the unit value for purposes of depletion, and the depletion allowance for the taxable year may be computed by multiplying such unit value by the number of units of mineral extracted during the year." This is simple, but is it reasonable? The intent of the law is clearly that the cost of the ore in the ground shall be considered as part of the cost of the same ore when removed and sold. The regulations fail to carry out that intent, because of the unwarranted assumption that all the ore in the mine cost the same amount per ton. This is what gives the Treasury Department's method its simplicity, but at the same time robs it of its reasonableness because the assumption is contrary to fact. It is self-evident that a ton of ore near the surface or exposed by present workings is worth much more than a ton buried so far down in the earth that it cannot be removed for many years. If no improvements in mining methods were expected, the value of deeply buried ore would be further reduced by the greater expense that would be required to

Jan 1, 1922

By M. R. Moharam

The well-known formulae of screening efficiency and circulating load calculations in closed crushing circuits were exploited to achieve graphical estimation of these parameters. Three basic charts were proposed and constructed. The first one is for the regular closed circuits where the new feed goes to the crusher. The second is for the reverse closed circuits in which the new feed reported to the screen is free of screen undersize particles. The third chart controls the reverse circuits when they are receiving new incoming feeds containing undersize material. Compound circuits were also reanalyzed and a concept of equivalent simple circuit was introduced to enable graphical manipulation of these complex circuits with the help of the aforementioned charts

Jan 1, 1982

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 William B. Plank

PRESENT enrollment of 182,361 students in the engineering schools of the United States and Canada represents an increase of 6.6 pct over the enrollment in these schools in 1951-52. Thus is brought to a halt the steady decrease in engineering enrollment that began with the close of the 1947-48 academic year, five years ago. The mineral engineering student picture is similarly encouraging. In the United States schools, 9453 students are preparing themselves for positions in the Mineral Industry. This is an increase of 8.3 pct over last year as compared with an increase of 6.6 pct in the total United States engineering enrollment. The rate of recovery for the mineral engineering group is thus more rapid than for the engineers as a whole.

Jan 4, 1953

By L. R. Flint, W. L. Freyberger, W. J. Howarth

W. L. Freyberger (Director, Institute of Mineral Research, Michigan Technological University, Houghton, Mich.)-The authors are to be complimented on their theoretical analysis of a column flotation process, and the comment I wish to make is not related to that analysis, but to the use of the word "countercurrent" to describe that process. Strictly speaking, the process the authors have described is countercurrent only in the sense of particle-bubble contact. That is, as solid particles and air bubbles pass through the column, the leanest flotation feed (the tailing) comes in contact with the greatest concentration of mineral-free bubbles. However, air bubbles alone do not comprise the complete extracting phase in a flotation system. A second component of this extracting phase is the collector, which is really the extractant inducing transfer of mat-

Jan 1, 1972

Those in charge of the Second Pan-American Financial Conference say that the engineering profession will be well represented at the Janu-ary conference in Washington. Latin American engineers are more closely connected with important industrial projects and have a greater command in matters pertaining to the developments on which they are working than is the case in the United States. Our own engineering profession may. therefore do well to study the Latin-American plan of cooperation between capital and the engineers.

Jan 11, 1919

By Paul M. Tyler

YEAR after year, the kaolin industry of the United States has been setting new production records and making better products. High-grade paper, pottery, and rubber clays are produced in this country mostly in the South. Georgia alone contributes over 70 pct and South Carolina almost 20 pct of the total domestic output. Residual kaolin is mined in North Carolina, highly plastic but naturally sandy Tertiary (Eocene) potting clays are worked in north central Florida, and good white clays are produced in several other states, but the main sources of kaolin or china clay have been numerous deposits in the Tuscaloosa (Upper Cretaceous) formation. This formation of generally sandy sediments is called the Middendorf member in older geologic reports and corresponds in age with some of the New Jersey clays. As shown in fig. 1, it crops out almost continuously in a generally southwesterly direction across South Carolina and Georgia and into Alabama. Clay is mined from this formation in all three states but the principal producing centers lie within about 10 miles of a straight line drawn between Aiken, S. C., and a point about 10 miles south of Macon, Ga. The white kaolins of the South were recognized and used prior to the Civil War but suitable treatment processes were not introduced until World War I when imports, chiefly from England, were curtailed. Although imports of high-grade clays were resumed after 1918, the domestic industry managed to treble its prewar production record during the early 1920's and has continued to grow. Whereas the 1909 to 1913 average total production in the United States was only 132,104 short tons valued at $705,352 f.o.b. mines, the output in 1948 was 1,568,848 tons worth $19,756,738.

Jan 6, 1950

By H. E. Lee, P. C. Feddersen

Greenockite is the only known cadmium mineral of importance. It occurs rather universally, in minor concentrations, as a secondary mineral in sphalerite deposits. The world's cadmium output is obtained through the processing of metallurgical by-products, largely from the treatment of residues from electrolytic zinc, retort zinc and lithopone plants. These sources are supplemented by the processing of fumes from lead and copper smelting operations. The development of modern selective flotation practice in the decade 1920-1930, which permitted the economical mining of complex lead-zinc ores, resulted in significant increases in the quantities of cadmium entering lead smelting systems. Being closely related to zinc as to occurrence, properties and production, most detailed description of cadmium recovery methods are to be found recorded in connection with zinc metallurgy. Other than occasional articles pertaining to particular operational procedures, literature offers but little in the nature of a balanced survey of lead smelter cadmium recovery practices. While many of the basic operations described for the recovery of cadmium from zinc by-products are applicable to the treatment of lead plant products, the inherent problems involved differ widely. In general the cadmium content of related by-products from routine lead smelting operations is present in lower concentrations, exists in a less soluble state and is associated with both a greater quantity and a greater variety of detrimental impurities. To cope with these problems, lead smelter practices are found to follow the general outline: Preparatory Processing 1. Concentration operations 2. Sulphation operations Cadmium Plant Processing 1. Leaching operations 2. Purification operations 3. Sponge precipitation operations 4. Metal recovery operations 5. Refining and casting operations As in the case of related zinc plant operations, cadmium recovery practices at lead smelters are not standardized. They not only vary as to type, but also extent. Depending upon prevailing conditions, lead smelter cadmium operations range from simple concentration campaigns, for the purpose of sufficiently "up-grading" products for shipment elsewhere, to complete processing steps for the production of refined metal. Preparatory Processing The cadmium content of lead smelter receipts is low and, as a rule, proportionate to the zinc content; the usual range of cadmium contained being of the order of 0.01-0.05 pct. Were it not for the low boiling point of cadmium, such small concentrations would, no doubt, be lost in the large tonnages of slag, metal and other smelter end products. However, the ready volatility of cadmium and its compounds at prevailing lead smelting temperatures results in its concentration in fractional portions of fume collected. This collected fume comprises a circulating load within the smelter system. Thus, the cadmium content of blast furnace fume* increases with each successive circulation until an equilibrium value is reached when the sum of the cadmium losses, due to handling and in slag, waste gases and other end products, becomes equal to the intake as ore. With ore receipts averaging, say 0.03 pct cadmium, the concentration value obtainable, through fume circulation in a routine manner, approaches 10-12 pct. In such operations, cadmium concentrations in blast furnace fume of from 3-5 pct are readily .attainable. However, the concentration gain beyond this range, with each additional circulation, is progressively decreased as a result of mounting losses occurring through handling and in end products. Therefore, to avoid excessive cadmium loss and to enhance the ultimate concentration anttainable, it is customary practice to isolate blast furnace fume at some intermediate cadmium content for special concentration procedure. The most common type cadmium concentration "campaign" involves special smelting operations wherein a relatively high portion of blast furnace fume at 3—6 pct cadmium is incorporated into the sinter charge. This type practice is roughly illustrated by the diagram on p. 111. Cadmium fume collected from lead blast furnace operations is not amen-

Jan 1, 1950

By Charles L. Elliot

Worldwide manpower utilization reached a new high at 10,482 professional man-months and expenditures increased to $19.9 million for mining geophysical activity during 1965. This is up from 9323 man-months and $14.5 million in 1964. Worldwide geophysical activity measured in percent distribution of the total manpower utilization and expenditures is presented in the accompanying Figs. 1 and 2. In terms of the total manpower utilization, ground surveys accounted for 61%, airborne surveys 18%, and mining geophysical research activity 21%. For expenditures, the breakdown was ground surveys, 49%; airborne surveys, 3901o; and research, 12%. Industry was responsible in general for 74% of the manpower utilization and 80% of the expenditures. Manpower costs in 1965 averaged $1900 per professional man-month.

Jan 11, 1966

By George Mah, Charles Wert

Internal-friction peaks caused by diffusion of oxygen and nitrogen have been observed in ytterbium. They are thought to be caused by the redistribution, under stress, of strain dipoles around an interstitial oxygen or nitrogen and a neighboring substitutional impurity. With the use of a simple geometrical model, diffusion coefficients for oxygen and nitrogen between special interstitial sites have been calculated. a) APPLICATION OF INTERNAL FRICTION TO MEASUREMENT OF DIFFUSION RATES IN DISSOLVED INTERSTITIAL ATOMS In bcc metals, the interstitial atoms occupy the centers of cube faces (0, 1/2, 1/2), or their equivalents, the center of the cube edges (0, 0, 1/2). An interstitial atom in this position causes an aniso-tropic distortion in the lattice. When stress is applied, mechanical relaxation can take place by the movements of the interstitial atoms. This relaxation has been used to obtain information concerning the movements of the interstitial atoms in the bcc metals. Data for these alloys have been compiled by Stanley and Wert. Other researchers have extended the investigation of interstitial diffusion to the close-packed metals. Gupta and weinig2 found an oxygen peak in a titanium, the height of which is linearly dependent on the oxygen concentration. They assumed, therefore, that they were dealing with movement of atomic ally dispersed oxygen in titanium. KG and wang3 determined that the diffusion coefficients of carbon in fcc steels and in nickel obtained by internal-friction methods were consistent with those obtained by macrodiffusion methods at much higher temperatures. Bisogni found oxygen and nitrogen peaks in hafnium by use of which he deduced the diffusion coefficient of these gases in hafnium. He observed further that the half-widths of these peaks corresponded almost exactly with those of a single-relaxation process; he assumed it to be caused by movement of atomically dispersed oxygen and nitrogen. From these studies, the deduction can be drawn that, in general, diffusion data can also be obtained for the interstitial diffusion in close-packed metals (or more precisely, in slightly impure close-packed metals). One group of such metals for which little data exist for the diffusion of dissolved oxygen and nitrogen is the rare earths. They have great affinity for gases, which enter solution interstitially. In this investigation results were obtained for the Yb-O and Yb-N interstitial solid solutions with traces of substitutional impurities; these solid solutions are of fcc structure. b) MECHANISM OF THE RELAXATION IN FCC CRYSTALS In the fcc structure, an interstitial gas atom is usually situated in the octahedral position (1/2, 1/2,

Jan 1, 1964

By Yoichi Ishida, Ching-Yao Cheng, John E. Dorn

Tile creep behavior of a iron was investigated over the range of temperatures from 375° to 1150°K. Apparent activation energies for creep, obtained by the effect of sudden changes in temperature on the creep rate, revealed the presence of- four distinguishable regions. The creep behavior of a iron in Regions II (480° to 774°K) and 111 (775° to 1045°K) was found to correlate well with a model where the creep rate is controlled by the nonconsevualive motion. of jogged screw dislocations. An anomalous increase in the apparent activation energy fur creep in Region III was found to be in harmony with the known decrease in the free activation energy for self-diffusion over the Curie transformation range. Furthermore, the creep rates in Regions II and III were found to increase with stress due not only to the effect of stress on the activation energy but also to an increase in density of mobile dislocations. The evidence suggests that pipe diffusion along moving dislocations could be a significant factor over the lower temperatures of Region II. ALTHOUGH the creep properties of iron and steel have been of interest to metallurgists for some time and an extensive literature is now available, most of the published information has not produced much toward understanding the fundamental dislocation processes controlling the creep behavior of these materials. Whereas the activation energy for high-temperature creep of metals usually agrees well with that for self-diffusion, Sherby, Orr, and Dorn1 deduced from the data of Tapsell -and c1enshaw2 that the activation energy for creep of Armco iron is about 78,000 cal per mole and more recently Lytton and sherby3 reviewed the data of Jenkins and Mellor4 and found an activation energy for creep of a iron of 80,000 cal per mole. Both values are substantially greater than the activation energy for self-diffusion in a iron. Because of the limited data suitable for purposes of identifying the controlling dislocation mechanisms of creep and the unusually high activation energies for creep quoted above, it was considered desirable to reinvestigate in detail the creep of a iron by more reliable techniques which would provide sufficient data for determination of the creep mechanisms. EXPERIMENTAL TECHNIQUE Creep specimens were prepared from 3/8 by 4 in. iron bar stock of the following composition by weight percent: 0.001 C, 0.0120 0, 0.001 N, 0.004 S, and 0.003 P. The as-received bars were cold-rolled to a thickness of 0.100 in., annealed under argon for 30 min at 1113°K, cold-rolled to a final thickness of 0.063 in., and machined into tensile specimens having gage section 0.250 in. wide and 1.70 in. long. Finally they were recrystallized under argon at 1113°K. Specimens to be crept above 1060°K were recrystallized at 1173°K. Both recrystallization treatments gave the same reproducible equiaxed ASTM No. 4 grain size. Creep testing was conducted in machines fitted with Andrade-Chalmers arms that maintained a constant stress to within ±0.2 pct of the reported values. Deformation over the specimen gage section was sensed with a linear differential transformer and recorded auto-graphically as a function of time. The strains deduced from these measurements were sensitive to ±5 x 10-5. During creep the specimens were contained in an argon-filled chamber which was immersed in a temperature-controlled molten tin bath. Creep temperatures, as measured by thermocouples attached to the specimen, were maintained to within ±10.25°K of the reported values. For activation-energy determinations rapid changes in temperature of about 12°K were obtained within 30 sec by direct resistance heating of the creep specimen, and maintained to ±1°K of the reported values. Observations of structural details of specimens before and after creep tests were made by electrolytic polishing and etching in acqueous ammonium persulfate. EXPERIMENTAL RESULTS A typical example of the determination of apparent activation energies, Q, by the effect of small changes in temperature is illustrated in Fig. 1. Q is defined by

Jan 1, 1967

By Walter Crafts

ALTHOUGH many elements reduce the tendency to porosity in steel castings, manganese, silicon, aluminum, calcium, titanium and zirconium appear to be most generally suitable for the purpose. The manganese and silicon contents are usually maintained in a fairly constant range. Sili-con-killed castings often are made to be sound with little or no addition of the stronger degasifiers. In many cases, however, it is more practical to utilize the stronger degasifying elements, aluminum, calcium, titanium and zirconium. Since they greatly modify the composition, shape, and distribution of the nonmetallic inclusions, and thereby the ductility, the strong deoxidizers must be used in such a way as to form the least harmful types of inclusions. As the reasons for failure always to obtain good results have not been obvious, an effort has been made to determine the mechanism of solidification of steels deoxidized to produce certain types of inclusions. Diagrams representing the mechanism of their formation have been constructed from the appearance of the nonmetallic con-stituents and have not only illustrated the limiting features of specific deoxidizing treatments with respect to inclusion formation and ductility, but have also indicated a relation between inclusions and resistance to hot tearing. Three different types of deoxidation treatment have been used for obtaining sound castings with relatively high ductility. The first method is to make and cast the steel under such conditions that deoxidation with silicon and a small addition of a strong deoxidizer assures soundness. The effective addition that will promote soundness without causing the formation of intergranular inclusions varies with the furnace practice and composition, but may be limited to about 0.025 per cent Al, Zr or Ti. Up to 0.10 per cent Ca and 0.15 per cent V are also used for this purpose. The inclusions in these steels are characteristically glassy silicates and round or irregular sulphides. As pointed out by Sims and Lillieqvist,1

Jan 1, 1940

By Frank Firmstone

By P. G. Shewmon

If interfacial equilibrium is maintained at the interface between a growing precipitate and the supersaturated matrix, so that solute diffusion alone determines the growth rate, the precipitate shape should evolve toward that characteristic of the dendrites found in solidification. However, this shape is rarely observed in precipitation reactions proceeding at high temperatures where interfacial equilibrium is usually felt to prevail. Thus some other stabilizing factor must enter, to keep the interface smooth. It is shown that a slow interfacial reaction (low interfacial mobility) will stabilize the interface, while transformation stresses have a IN studying the kinetics of phase transformations such as solidification or proeutectoid precipitation at high temperatures, it is customary to assume that equilibrium exists across the interface and that the rate of the reaction is determined by the rate at which heat and solute diffuse to and from the interface. In the case of precipitation, such an assumption predicts an almost infinite rate of initial growth. It is generally stated that the rate cannot be infinite and that during some initial period the rate must be determined not by solute diffusion but by an interfacial reaction, i.e., transferring atoms across the interface. The duration of this much weaker stabilizing eFfect and impurities tend to enhance instability. It is also concluded that a sets an upper limit on the wavelength of the perturbation that can give instability. Thus initially all flat or smoothly curved particle interfaces will be stable even if their growth is diffusion-controlled. Proeutectoid precipitation in the Fe-C system is considered in some detail and it is shown that the experimental results can only be rationalized if the growth rate of ferrite in steel transformations is determined by a slow interfacial reaction for all hut a few orientations between the two phases. initial period has never been clearly established, but it is generally assumed to be too short to affect any measurable results.' Several authors have pointed out that in the case of interfacial equilibrium any bump in the surface will grow out ahead of the planar interface due to the higher gradient in front of it.2j3 Thus the interface will be unstable with respect to an irregular interface with points (plates) propagating rapidly out ahead of the interface into the supersaturated phase. Recently, Mullins and Sekerka have given equations for the stabilizing effect of surface tenion.~ They found that for particles with a radius of curvature of 1 p or greater the stabilizing effect of surface tension will be completely overcome by a supercooling, or supersaturation, of as little as

Jan 1, 1965

By K. J. Powers

The Mine Accident, Injury, Illness and Employment Database at the Mine Safety and Health Administration's Health and Safety Analysis Center is a computerized system that stores accident, injury, illness and employment data about all coal and metal/nonmetal mines in the United States. The paper discusses the system for collecting, storing, analyzing, and reporting this information and how these data are used in the ongoing effort to increase the health and safety in this nation's mines.

Jan 1, 1983

By J. Charles Miller

Natural carbon dioxide has recently been exploited in the United States in consequence of oil and gas developments in the Western States and the growing demand by transcontinental and transoceanic shippers for solid carbon dioxidc. The discovery by drilling of commercial deposits resulted in consideration of its geographic and geologic distribution and occurrence. Its wide distribution in nature is evidenced by its occurrence in the atmosphere, hydrosphere and lithosphere. The question of origin of carbon dioxide involves consideration of theories similar to those concerning natural hydrocarbons, although available evidence favors an inorganic rather than an organic source. Areas favorable to development of commercia1 production appear to be those in proximity to igneous rocks or in the vicinity of decadent volcanic activity, where, it has long been known, the gas is evolved either free or dissolved in the waters of fumaroles, geysers or mud pots. Structure contour maps are presented showing the Wagon Mound anticline in New Mexico and the Farnham anticline, Utah. A well drilled on the latter supplies gas to a 20-ton plant manufacturing solid carbon dioxide at Wellington, Utah, on the Denver and Rio Grande R.R., whence it is shipped to surrounding territory and to the West Coast. Before funds are invested in a plant for the manufacture of liquid or solid carbon dioxide, whether supplied by wells or springs, an effort to ascertain the volume of gas available is advisable. The use of present methods of estimation of gas reserves with modifications to account for the quantity absorbed by any water present in the producing formation is recommended. The Farnham anticline is used as an example and computations are made of the probable volume of gas originally present in the structure. No attempt was made to compute reserves in the Niland area, California, for the reason that in such areas it is believed the volume is indeterminate. Introduction Carbon dioxide, in liquid and solid form, has found a wide variety of uses other than its primary application in carbonating beverages. It is now used in more than 40 different ways, ranging from cooling or freezing to use in gas or liquid form for mechanical purposes, chemical industry, explosive, fire extinction, and tire manufacturing. Undoubtedly the chief supply of carbon dioxide is obtained from industrial plants or artificial sources and until recently natural deposits of the gas have received little consideration. Few will question the utility and perhaps dependability of artificial sources, which possess the advantage over

Jan 1, 1941

By J. Charles Miller

Natural carbon dioxide has recently been exploited in the United States in consequence of oil and gas developments in the Western States and the growing demand by transcontinental and transoceanic shippers for solid carbon dioxidc. The discovery by drilling of commercial deposits resulted in consideration of its geographic and geologic distribution and occurrence. Its wide distribution in nature is evidenced by its occurrence in the atmosphere, hydrosphere and lithosphere. The question of origin of carbon dioxide involves consideration of theories similar to those concerning natural hydrocarbons, although available evidence favors an inorganic rather than an organic source. Areas favorable to development of commercia1 production appear to be those in proximity to igneous rocks or in the vicinity of decadent volcanic activity, where, it has long been known, the gas is evolved either free or dissolved in the waters of fumaroles, geysers or mud pots. Structure contour maps are presented showing the Wagon Mound anticline in New Mexico and the Farnham anticline, Utah. A well drilled on the latter supplies gas to a 20-ton plant manufacturing solid carbon dioxide at Wellington, Utah, on the Denver and Rio Grande R.R., whence it is shipped to surrounding territory and to the West Coast. Before funds are invested in a plant for the manufacture of liquid or solid carbon dioxide, whether supplied by wells or springs, an effort to ascertain the volume of gas available is advisable. The use of present methods of estimation of gas reserves with modifications to account for the quantity absorbed by any water present in the producing formation is recommended. The Farnham anticline is used as an example and computations are made of the probable volume of gas originally present in the structure. No attempt was made to compute reserves in the Niland area, California, for the reason that in such areas it is believed the volume is indeterminate. Introduction Carbon dioxide, in liquid and solid form, has found a wide variety of uses other than its primary application in carbonating beverages. It is now used in more than 40 different ways, ranging from cooling or freezing to use in gas or liquid form for mechanical purposes, chemical industry, explosive, fire extinction, and tire manufacturing. Undoubtedly the chief supply of carbon dioxide is obtained from industrial plants or artificial sources and until recently natural deposits of the gas have received little consideration. Few will question the utility and perhaps dependability of artificial sources, which possess the advantage over

Jan 1, 1941

By F. C. Greene

The oil and gas industry in Missouri in 1934 continued along the same lines that have marked the previous years. One new gas pool has been opened, others have been extended and in one oil pool a 25-bbl. well was completed. Missouri has no laws or regulations relating to drilling or the filing of well logs and the Geological Survey depends on its own scouting activities to obtain information. The data herein have been taken largely from a paper by the author recently published in the 58th Biennial Report of the State Geologist of Missouri. That report is available on application to H. A. Buehler, State Geologist, Rolla, Missouri, accompanied by ten cents in stamps, the amount of the postage. The preliminary figures, subject to revision, indicate that before the end of December, 1932, there were 2495 completions, of which 320 were oil wells, 1139 were gas wells and 1036 were dry. Over half of the oil wells were drilled in the Richards-Stotesbury area of Vernon County and were pumped for only a short period of time. During the period 1933-34 there were 201 completions, of which 10 were oil wells with an initial daily capacity of 100 bbl., 90 were gas wells, with an open flow of 26,578,256 cu. ft., and 101 were dry. The most active areas in drilling for gas in 1934 were the Marota area, sec. 17, T.49N., R.32W., Jackson County, the Grandview area in T.47N., R.33W., Jackson County, and the Plattsburg area in Clinton County. The Knoche oil pool in sec. 16, T.46N., R.33W., Cass County, was the scene of the only important oil development. In the Marota pool nine wells were completed to the Squirrel sand, with a combined open flow of about 5,000,000 cu. ft. The pool is on a small symmetrical dome with a closure of at least 30 ft. The average depth of the wells is 450 ft. The Squirrel sand (Upper Cherokee, Pennsylvanian) had a thickness of 94 ft. in a near-by dry hole, but only the upper 30 or 40 ft. is drilled in the producing wells. The largest well

Jan 1, 1935

By Horace Knerr

The term. "high-yield-strength," used in the title of Dr. Gillett's paper (p. 40) is obviously relative. His discussion is limited to improved steels intended to compete with the low-cost, low-carbon, hot-rolled, sheet and plate steels of commerce made and used on a tonnage basis, without heat-treatment. In his list of about three dozen steels, only three have a yield strength of 70,000 lb. per sq. in., or over. Double such values are not uncommon in aircraft steels. Dr. Jeffries (p. 21) refers to "light-weight metals," obviously meaning strong alloys of low specific gravity; namely, aluminum alloys of the duralumin type and certain magnesium alloys. In a structural material, "lightness" is determined by two factors, strength and specific gravity. They must always be considered jointly. The basis of comparison is a strength-weight ratio, obtained by dividing the desired strength value, such as tensile strength, yield strength, or endurance limit, by weight per unit of volume, such as specific gravity or pounds per cubic inch1. For example, aluminum is a heavy metal, structurally, unless alloyed and heat-treated to give it high strength. When the strength of a structural metal is raised by heat-treatment or by cold-work, its specific gravity is not appreciably changed, but it is made lighter in direct proportion to the increase in strength because less of it will be required to carry the load. The lightness of the finished structure of adequate strength is the real point of interest. This structure must not only carry designed load, but "stand the gaff" of service, which includes the effects of accidental overload, fatigue, corrosion, loosening of joints, and so forth. Neither Dr. Gillett nor Dr. Jeffries mentions the true "lightest material of construction," which is alloy steel, tubular in form (Fig. 1), assembled by welding and heat-treated to a yield strength in excess of 150,000 lb. per sq. inch.

Jan 1, 1936