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By P. D. Merica

IN connection with other investigations on the properties and characteristics of chilled iron car wheels, the question as to the best range of annealing temperatures was raised. Chilled-iron wheels are cast with a chill against the tread and the inside of the flange, the remainder being in sand. The composition of the metal is so chosen that under these conditions the tread and inside of the flange will show white iron to a depth of from 5/8 to 7/8 in. (15 to 22 mm.), the remainder of the wheel becoming graphitized or gray. In order to relieve the stresses set up during cooling under such drastic conditions, the wheels are stripped from the mold, while still red hot, piled in a soaking pit, and allowed to cool very slowly from their temperature at stripping. Obviously the most suitable temperature for this annealing is the highest at which no formation of graphite occurs within the white tread and at which the wheels can be stripped from the molds. Inasmuch as no direct determinations have been made of the temperatures at which the' formation, of graphite takes place in white iron of compositions used in car wheels upon annealing, it was considered worth while to determine these temperatures as a means of establishing the maximum temperatures at which the annealing of the wheels may be carried out. In the course of this work, some incidental observations were made which are of interest in connection with the theory of graphitization in white iron. The literature on the subject of the formation of graphite both during cooling at casting and upon annealing is very extensive and can be best studied by reference to a comprehensive discussion of the subject by Hatfield. 1 Perhaps the most important contributions of previous investigation are the following: 1. Whether a given mass of molten iron becomes white, mottled, or gray upon casting, depends on its composition and its rate of cooling through the temperature range of solidification and immediately below.

Jan 7, 1919

By A. J. Miller, G. R. Brophy

THE Grossmann principle1 for the calculation of hardenability of steel from composition is attractive because of its simplicity. It postulates that the hardenability of a steel for any particular grain size may be expressed in terms of an ideal critical diameter, which is the product of an ideal critical diameter for a "pure" iron-carbon base multiplied by a succession of factors for each element of composition contained, including the incidentals. It infers that the multiplying factor for a given quantity of an element is constant for all combinations of composition. Grossmann has stated that in the great majority of cases the experimental values of hardenability are found to be well within 10 per cent of the calculated values. The validity of the scheme has been confirmed in principle by Crafts and Lamont2,3 and by Kramer et al .4 Their results differ from the original in the magnitude of the effect of some elements but, since they accepted the product concept and followed its direction, it is to be expected that similar results would be obtained. Crafts and Lamont, in their second paper, recognized that the factor relations for manganese and nickel were not continuously linear, but beyond certain critical amounts increase sharply. Austin, Van Note and Prater5 demonstrated nonlinear relations between hardenability and alloy contents. Their curves for chromium, silicon, manganese and nickel were all convex upward to show decreasing incremental effects. They concluded that Grossmann's factors underevaluate the hardening effect of low percentage additions of these elements, and overevaluate the larger additions. [ ] More recently W. Steven6 has found that the factor method fails when applied to complex steels containing two or three principal alloying elements other than carbon. Multiplying factors derived from his results bear a complex relation to composition and are not constant for a given amount of an element as the base composition varies. C. A. Liedholm7 found that, using either the Grossmann or the Crafts-Lamont multiplying factor values, not only were

Jan 1, 1945

By T. S. Lundy, F. R. Winslow

DIFFUSION coefficients of Hf181 in the high-tem-perature bcc phase of reactor-grade hafnium were determined at temperatures of 1795° to 1995°C by standard lathe-sectioning techniques. The temperature dependence of the data may be described by an Arrhenius-type expression for this limited temperature interval. However, hafnium is classed with the "anomalous" bcc metals zirconium, titanium, and y uranium by the low values of Do and Q observed in this study. The hafnium metal was received as 1/2-in.-diameter crystal bar. Analyses by the Analytical Chemistry Division of Oak Ridge National Laboratory showed the major impurity to be zirconium— about 2.1 pct. The total interstitial content was about 225 ppm with 190 ppm of this oxygen. The Hf"' was supplied as HfC12 in HC1 solution by the Isotopes Division of Oak Ridge National Laboratory. The hafnium bar was cut into disk-shaped specimens 3/8 in. long. One of the flat faces of each specimen was metallographically treated and then the isotope was deposited by vacuum evaporation from a tungsten filament. A 3 by 3 in. NaI (Tl) crystal with a single-channel analyzer was used for counting y rays with energies of 0.3 to 0.7 Mev. The as-deposited layers of isotope had counting rates of about 200 counts per sec. Specimens were annealed in argon in a tantalum resistance furnace. Temperatures were measured with a microoptical pyrometer calibrated for the particular furnace sighting conditions. All sectioning was done by standard lathe techniques. Section weights were determined on a semimicrobalance. A density of 12.5 g per cu cm was used in determinations of section thicknesses. Activities associated with the various sections were measured and the penetration data were treated using the computer code by winslow.' In all cases, except for specimens annealed at temperatures below 1795°C, normal Gaussian penetration behavior resulted. At lower temperatures, plots of In A(x) vs x2 were nonlinear [~(x) = relative activity at a distance x from the

Jan 1, 1965

By Edward G. Norton

The salt deposits of the Mississippi Embayment region present a problem of origin so genetically related to the larger problem of the stratigraphy and structure of the region that a discussion of the one necessarily involves or assumes an understanding of the other. For this reason, I shall summarize briefly our knowledge of this region, emphasizing the facts related to the subject of this paper. In so doing I shall make liberal use of the reports of the National and State surveys. Geographically that section of the United States known as the Mississippi Embayment region represents a great V-shaped area, extending from near Cairo, Ill., to the Gulf of Mexico, and including Louisiana, eastern Texas, all that part of Arkansas bordering the Oua-chita and Ozark mountains, western Tennessee, Mississippi, and a part of Alabama. This great section Professor Harris has described as structurally a pitching trough, its medial line being well represented by the Mississippi River. Outcropping along the border of this area are the Cretaceous and Tertiary formations, unconformably laid down on the hard Paleozoic rock sheets that show more or less plication, deformation, and faulting, depending upon their proximity to the nearby major uplifts. East and west of the Mississippi River the Cretaceous and Tertiary beds dip river- and coastward at angles greater than the slope of the land. "Waters entering along the outcropping edges of the Tertiaries and Cretaceous and following bedding planes southward are soon thousands of feet beneath the surface." As the sedimentation of the region progressed, faulting and slips occurred along planes of pre-Cretaceous weakness. Whether these movements were genetically related to the loading of this V-shaped area, as Professor Harris seems to think, is a question still to be settled. The accompanying map, Fig. 1, was taken from Bulletin No. 7 of the Louisiana- Geological Survey. It shows the regional distribution of the salines, as well as an alignment of the domes, which has been assumed to indicate faulting.

Jan 1, 1915

By Russell Franks

IN recent years a considerable tonnage of the 18 per cent chromium and 8 per cent nickel steels has been used in lightweight high-strength structures that must be resistant to deterioration under atmospheric conditions. These steels are austenitic in character and their strength can best be increased by cold-working. Although a marked increase in tensile strength is obtained, claims have been made that the cold-worked steels do not possess fully satisfactory elastic properties. Under certain conditions, however, this has caused no great concern, because, as explained by Ragsdale,1,2 the cold-rolled steels have been widely applied for construction of lightweight, high-strength trains using spot welding for joining purposes. Ffield3 agrees that the ease with which thin sections of the cold-rolled 18-8 steels can be joined by spot welding is greatly in their favor, but that they would be more satisfactory if higher elastic properties and a higher modulus of elasticity could be obtained. He states that, as far as the mechanical properties are concerned, the straight chromium stainless steel is superior to the cold-worked 18-8 steel, and in order to illustrate, he presented the data of Fig. 1, which also give a stress-strain curve for a low-carbon 13 per cent Cr steel. Ffield? pro-posed that columbium-bearing or titanium-bearing cold-rolled 18-8 steels be given a heat-treatment (preferably for 1 hr.) in the range 400° to 600°C. to precipitate carbides in order to obtain better mechani-cal properties. Discussions by Sutton,4,5 de Ganahl,6,7 8 Krivobok and Lincoln,9 Knerr,10 and Thaden11 have given further information on the properties of the cold-rolled 18-8 steels compared with other materials used in light-weight, high-strength structures. These investigators and others point out that the ultimate tensile strength of the cold-rolled 18-8 steel can be increased to 200,000 lb, per sq. in. or higher; Krivobok et al. indicate that

Jan 1, 1940

By J. P. Van Kleunen

9.3-1. Introduction. The demands of industry for handling materials at higher rates and at reduced costs have had a very significant effect on belt conveyor technology. Although the general appearance of the belt conveyor today is essentially the same as it has been for the past several decades, the similarity ends there. Each component comprising the conveyor system has been continuously improved through design and materials technology to enable present conveyor systems to operate at ever-increasing rates and reliability. For example, twenty years ago the strongest commercially available, fabric-reinforced conveyor belting had a tension rating of 50 lb per ply-in. Currently, fabric-reinforced belts are available with ratings of 350 lb per ply-in. and steel cable reinforced belting is available with tension ratings of 3000 lb per in. of belt width (3). These technological advances have therefore enabled the belt conveyor to not only attain acceptance as a preferred method for in-plant movement of bulk materials, but also to be used for long distance transportation of bulk materials, particularly in areas of adverse terrain. The information contained in this chapter is intended to assist the reader to make basic decisions regarding the use and application of a conveyor system. The design of an overland conveyor transportation system or an in-plant process conveyor is accordingly beyond the scope of this article. Many comprehensive technical works covering the design of a belt conveyor are currently available from the manufacturers of materials handling equipment (6, 7, 9, 11). The design handbook published by the Conveyor Equipment Manufacturers Association is particularly recommended (2). 9.3-2. Conveyor Capacities. One of the most important factors in determining the proper size of a conveyor system is the rate at which material must be handled. Although tables and charts are available to the conveyor designer to assist him in his selection of conveyor components, only the

Jan 1, 1968

IN accordance with a programme arranged by a committee of the Institute, consisting of Mr. William P. Shinn, of St. Louis, chairman, and Mr. Joseph D. Weeks, of Pittsburgh, secretary, the member's of the Institute, with their ladies and invited guests, assembled in Chicago on Sunday morning, August 22d. A special train, provided by the Chicago and Northwestern Railway,. left Chicago on Monday morning at 7.50 o'clock, and conveyed the party to Marquette, arriving at 9 o'clock P.M. Here the steamer Northern Queen, which had been chartered by the committee for the accommodation of the Institute, was in waiting, and the members and ladies at once took up their quarters on the boat. EXCURSIONS IN THE MARQUETTE IRON REGION. Local Committee. EXECUTIVE. -J. C. Morse, chairman; C. Y. Osburn, secretary ; D. F. Wadsworth, treasurer; C. H. Hall, H. Merry. RECEPTION.-S. P. Ely, J. P. Pendill, E. Breitung, W. F. Swift, A. P. Swineford, J. C. Fowle, C. G. Griffey. TRANSPORTATION.-Samuel Schoch, D. Morgan, D. H.. Merritt, J. Pickands. FINANCE.-Peter White, A. W. Maitland, W D. Rees, E. R. Hall. EXCURSIONS.-W. E. Dickinson, H. A. Burt, A.. Kidder, C. E. Wright. REFRESHMENTS.-J. Q. Adams, H. H. Stafford, Joseph Kirkpatrick, D. H. Bacon. On Tuesday the iron mines in the vicinity of Negaunee and Ishpeming were visited, transportation being provided by special trains on the Marquette, Houghton and Ontonagon Railroad. In the morning the McComber, South Jackson, and Jackson mines were inspected, and in the afternoon the Cleveland, New York, Lake Superior, and Barnum mines. Dinner was provided at Negaunee, and gracefully served by, the ladies of the town. In the evening the first session of the Institute was held in the saloon of the steamer. The President, William P. Shinn, of St. Louis, congratulated the Institute on the happy consummation of the wishes of its members to have a meeting on Lake Superior. After tedious and baffling negotiations arrangements had been com-

Jan 1, 1881

By Kenneth Cottingham

The year 1941 brought a considerable increase in drilling activity in Ohio. In 1940, the total of wells completed was 1228, whereas in 1941 it was 1561, or an increase of approximately 27 per cent. Of the 1561 wells, 333 were oil wells, 701 gas wells and 527 dry holes. The completions for the past five years are shown in Table I; the number of productive oil or gas wells for the year 1941, arranged by producing formations, are given in Table 2; the number of wells, oil, gas or dry, completed in each county in 1941, in Table 3, and wells by sands in Table 4. The production of oil increased by about 500,000 bbl. in 1941, nearly all of the increase being in Pennsylvania grade. In 1940, the total production was 3,052,000 bbl. from 25,500 wells. In 1941 the total production was 3,547,534 bbl. from 24,801 wells. The increase in production is chiefly due to the Clinton pool in Clayton township, Perry County, which is briefly men- tioned later in this review. The number of oil wells, by grades of oil, and the total quantities produced are shown in Table ;. Annual oil production for five years is listed in Table 6. The average prices paid for crude in 1941 were slightly higher than in 1940 These 1941 prices, with dates of change, are shown in Table 7. The maximum production of natural gas in Ohio was in the year 1915, when the total was just under 80 billion cu. ft. The maximum consumption occurred in the year 1916, and was approximately 169 billion cu. ft. For the past several years, Ohio has ranged from eighth to eleventh, in order of gas production for the different states, being in tenth place in 1940. In the matter of consumption, however, Ohio remains in fifth place. Preliminary figures for 1940 indicate that production of natural gas increased II per

Jan 1, 1942

By Kenneth Cottingham

The year 1941 brought a considerable increase in drilling activity in Ohio. In 1940, the total of wells completed was 1228, whereas in 1941 it was 1561, or an increase of approximately 27 per cent. Of the 1561 wells, 333 were oil wells, 701 gas wells and 527 dry holes. The completions for the past five years are shown in Table I; the number of productive oil or gas wells for the year 1941, arranged by producing formations, are given in Table 2; the number of wells, oil, gas or dry, completed in each county in 1941, in Table 3, and wells by sands in Table 4. The production of oil increased by about 500,000 bbl. in 1941, nearly all of the increase being in Pennsylvania grade. In 1940, the total production was 3,052,000 bbl. from 25,500 wells. In 1941 the total production was 3,547,534 bbl. from 24,801 wells. The increase in production is chiefly due to the Clinton pool in Clayton township, Perry County, which is briefly men- tioned later in this review. The number of oil wells, by grades of oil, and the total quantities produced are shown in Table ;. Annual oil production for five years is listed in Table 6. The average prices paid for crude in 1941 were slightly higher than in 1940 These 1941 prices, with dates of change, are shown in Table 7. The maximum production of natural gas in Ohio was in the year 1915, when the total was just under 80 billion cu. ft. The maximum consumption occurred in the year 1916, and was approximately 169 billion cu. ft. For the past several years, Ohio has ranged from eighth to eleventh, in order of gas production for the different states, being in tenth place in 1940. In the matter of consumption, however, Ohio remains in fifth place. Preliminary figures for 1940 indicate that production of natural gas increased II per

Jan 1, 1942

By J. A. Holmes

Venezuela has continued during 1929 to demonstrate that it is destined for many years to come to be one of our most important sources of crude petroleum. The producing fields of the Bolivar Coastal district along the east side of Lake Maracaibo have continued their phenomenal production, and two new fields have reached the near producing stage, while the results of deep test wells have strengthened the predictions and expectations that oil will be found and produced from many other pools and from several different geological formations. The finding of these new oil pools is not going to be easy, because the surface evidences of geological structure are scanty, and the subsurface problems are difficult, but intelligent effort backed by ample resources may be counted upon to overcome these obstacles and lead to a continued increase in the number of producing fields in Venezuela. During 1929 the total production of Venezuela was approximately 135,953,000 bbl., an increase of nearly 30,000,000 bbl., or 28 per cent., as compared with the preceding year. During 1929 oil in steel storage in Venezuela decreased from 13,000,000 to about 11,000,000 barrels. Tables 1, 2 and 3 briefly summarize Venezuelan production by fields and by years, and show the trend of production since its establishment on a commercial basis. Table 1.---Production of Crude Oil in Venezuela by Years, 1917 to 1929 All Figures in Barrels of 42 Gallons Total PRodUction Total PRoduction Year VeneZUela, Bbl. Year Venezuela, Bbl. 1917....................... 227,000 1927.................... 63,181,000 1918....................... 368,000 1928.................... 106,000,000 1919....................... 258,000 1929.................... 135,953,000* 1920..................... 548,000 Grand Total Since Ineep- 1921...................... 1,544,000 tion................... 380,791,000 1922....................... 2,448,000 Increase, 1929 over 1928.. . 29,953,000 1923..................... 4,170,000 Per cent. Increase......... 28.2 1924....................... 9,234,000 Per cent. 1929 Production 1925....................... 20,219,000 of Total............... 35.7 1926....................... 36,641,000 * Includes estimate for closing period of 1929.

Jan 1, 1930

By Donald L. Katz

Charts for predicting the pressure to which natural gases may be expanded without hydrate formation have been prepared for gases of even gravity. Pressure-temperature curves for hydrate formation were established for gases having gravities from 0.6 to 1.0. These curves and the thermal behavior of the gases during free and adiabatic expansion were used to prepare the charts for estimating the permissible expansion of natural gases without hydrate formation. The problem was solved by L. F, Albright, W. T. Boyd, J. J. McKetta, G. Martin, P. Poettman. and A. P. Snyder.-, who are first-year graduate students in the department of Chemical and Metallurgical Engineering at the University of Michigan. This paper is essentially a summary of their results. Prediction of Conditions for Hydrate Formation in Natural Gases Each natural gas under a given pressure will form solid hydrates at a corresponding temperature provided sufficient water is present.1-5 The temperature of natural gases below about 5000 lb. per sq. in. decreases when the gases are expanded freely.6,7 This decrease in temperature may cause the expanding gas to enter the region of temperature and pressure at which hydrates will form' The final pressure to which a natural gas may 'be expanded without hydrate formation depends upon the initial temperature and pressure and the gas composition. This paper presents charts that give the final pressures to which gases of gravity 0.6 to 1.0 at given initial temperatures and pressures may be expanded without formation of hydrate. Hydrate-forming Temperatures and Pressures as a Function OF Gas -Gravity Experimental data of pressure versus temperature at which solid hydrate will form, provided sufficient water is present, are available for a series of gases.2,3 A method of predicting the pressure-temperature curve for a given gas composition has been reported.' The solution to this problem requires that these curves relating pressure to temperature be established for gases of given gravities.

Jan 1, 1945

By Percival Roberts

I DESIRE to present this evening a few notes from the standpoint of a manufacturer upon the subject of tests of iron for structural purposes; not that I have any new facts to which to call your attention, but rather a statement of a few of the objectionable features of the present modes of operation, showing the absolute necessity of important and very radical changes. At the present time, as most of you are well aware, proposals for materials are accompanied by certain specifications as to quality and tests to which the manufactured article must conform. Evolved in many cases from the inner consciousness of some one more expert in theory than in practice, we find a few of the specifications to be good, many bad, and some indifferent. Appended are specimens of specifications of the most prominent engineers and railroad companies, which may be taken as representing the best and most intelligently framed specifications which we now have, arid yet in some pints scarcely satisfactory, owing to misunderstanding of tests as now made. To show the very varied opinions held as to proper quality of iron for bridge-work, I give the tests of two lots of fron made by inspectors with the results, which were referred to the maker with the following commensts : Lot No. 1. Teat of Iron for Eyebars. Reduced area. Elongation. Size. Per cent. Per cent. Breaking load. 4" x 1 3/8 26 25 68,500 Bent 120° around 1 1/2" bar with fracture. Reduced area. Elongation. Size. Percent. Percent. Breaking load. 6" x 1 7/15 24 24 48,820 Bent 110° around 2" bar. This iron should bend 180° without fracture, and is therefore rejected. Lot No. 2. Test of Iron for Brirlye. All measurements taken upon a parallel section of 10". Iron for tension members. Breaking load Elongation. size. per aquare inch. Percent. 1 5/8 49,600 20 14 61,600 27

Jan 1, 1882

By R. V. Whetsel, Valentin R. Garfias

Mexican petroleum production for 1928 was approximately 50,000,-000 bbl., the lowest in 12 years, showing a decrease from 1927 of over 14,000,000 bbl. The steady downward trend for the past 7 years has allowed Russia to outrank Mexico by a wide margin for third position and if the expected decline continues during 1929 it should place Persia ahead of Mexico as fourth in rank. The year 1928 was characterized by a continuation of the reentrench-ment previously begun by the oil industry in Mexico in an attempt to adjust itself to the adverse conditions caused by the steady depletion of the fields, the rapidly increasing competition from Venezuela and the United States and the as yet unsettled petroleum legislation and taxation situation. With the exception of the Isthmus of Tehuantepee, drilling in proved fields was considerably curtailed and although the number of wildcats completed exceeded those of the previous year, no extensive drilling programs were undertaken. Practically without exception, the major companies reduced personnel and operations to a point where they could meet existing conditions and mark time while awaiting a more stable basis for the future testing of unexploited regions. Many terminal and transportation facilities were abandoned during the year. Development Only 371 wells were completed during 1928, as against 583 in the previous year and 808 during 1926, and although the percentage of producers in 1928 was 34 per cent., compared to 26 per cent. in 1927, the initial production of -wells was considerably lower than during the previous year, a great number of the wells showing salt water and becoming "strippers" from the time they started to flow. Development is summarized in Table 1. Drilling in the Northern fields did not prove any new pools of importance, the most successful wells being located in the old producing areas of Cacalilao, Panuco and Topila. (Fig. 1 Very few of the producers made more than 1000 bbl. daily, and a great many less than 300 bbl. a day.

Jan 1, 1929

By Richard Bosustow, Van Dyne Howbert

The Presidio mine of The American Metal Co. is situated in the "Big Bend" region, some 45 miles over state highway south of Marfa, a station on the Southern Pacific R.R. It lies 20 miles by road north of the Mexican border, in semidesert surroundings typical of this general section of the United States and the adjoining part of Mexico. All supplies are hauled in by truck from Marfa under contract. The concentrates and precipitates produced by the mill are carried by the same trucks to Marfa, from whence they are shipped, respectively, to the El Paso and Selby plants. History The mine was discovered about the year 1880 and was soon thereafter taken over for development by some army officers stationed at Fort Davis, Texas. It was later operated by the Presidio Mining Co., which treated the ore in a small pan-amalgamation mill from 1883 until 1913, when a cyanide plant was erected which has been in continuous operation ever since. When the present company, a subsidiary of The American Metal Co., Ltd., took over the mine in April, 1926, the ore-bearing zone had been worked for about 2200 ft. to the east of I the outcrops down the dip of the formation, at which point it is at a I vertical depth of 500 ft. below the surface. Up to that time the mine had produced some 1,150,000 tons of ore averaging about 17 oz. silver. After a development campaign the company started milling again in February, 1927. Since then the production has been approximately 4700 tons per month of ore; of which the yearly average grade has varied from 19.7 to 23.2 oz. silver, $0.20 to $0.50 gold, and 2.0 to 2.5 per cent. lead. No other property in this district has ever produced tonnage of any importance.

Jan 1, 1931

By Eugene A. Stephenson, Leon J. Pepperberg

The natural gas industry is essentially a byproduct of the oil industry. When first discovered the gas was usually regarded as a nuisance, and even when found immediately associated with oil, or suspected to be so, it was customary to blow it freely into the air, in the hope that gas would shortly be replaced by a flow of oil. The early methods of production,' transportation, and utilization were neither economical nor efficient; the chief value of gas was based on its use as a fuel, with no regard to (1) its effect. upon the oil with which it was associated, (2) its importance as a lifting agent, or (3) to its possibilities for the manufacture of byproducts. The spread of scientific research among major gas and oil companies, manufacturers, and academic groups, has gradually brought recognition of the fact that many of the technical problems bearing on production, transportation and utilization are common to both the gas and the oil industry. A few of the problems that have received serious study, and from which highly gratifying results have been obtained, are: (1) gas measurement, (2) oil well and gas well capacity tests, (3) elimination of field waste, (4) design of pipe lines and compressor stations, (5) extraction of constituents which might interfere with the normal flow of gas through the line, (6) control of reservoir pressure, (7) estimation of reserves of both oil and gas, (8) control of water encroachment, (9) measurement of factors which influence fluid movement through sands, (10) solubility of gases in oils, (11) effect of dissolved gases upon the properties of the solution. These investigations have demonstrated that almost every problem relating to oil production also involves some phase of natural gas engineering. During the past 15 years the use of experimental methods for the discovery and measurement of obscure, influencing factors, which cannot be determined purely by hydrodynamic or thermodynamic analyses, have contributed much towards the progress made in solving the problems of the oil and gas industries. Most of the experimental work on

Jan 1, 1934

By Alexander L. Holley

THE 400-ton testing machine, ordered in June, 1875, by the United States Board appointed to test "iron, steel, and other metals," has lately been completed at the Watertown Arsenal, thoroughly proved and accepted by the Board. The excellence of the machine in every respect is more than satisfactory, and its accuracy is at first sight astonishing, although an investigation of its principles must show that if the weighing apparatus will weigh at all, it must do so with perfect accuracy, because all its movements are absolutely without friction. The proof experiments were numerous, and the effects of recoil after sudden ruptures at maximum loads, were watched with great care, but without much anxiety, because the weighing parts affected are by no means delicate in structure, and their motion is almost infinitely small. Among the tests were the following : A forged link of hard, wrought iron, 5 inches in diameter between the eyes, was slowly strained in tension, and broke short off with a loud report at 722,800 pounds. The diameter before breaking at the point of fracture was 5.04 inches; after breaking, 4.98 inches. In order to see if the weighing parts had been disturbed by the recoil, which was obviously near the greatest recoil the machine will ever suffer, a horse-hair was next tested ; it was 7-1000ths of an inch in diameter; it stretched 30 per cent., and broke at 1 pound. Other horse-hairs vary in tenacity between 1 and 2 pounds. Of course, the accuracy of the machine on such delicate specimens, and indeed on specimens having some hundreds of pounds tenacity, has been checked and proved by other weighing machines. A 5-inch round bar, turned down to 3 5/8 inches diameter along the centre, was pulled apart at 430,200 pounds tension. Then some more horse-hairs were tested ; also copper wires 19 1/2-1000ths of an inch in diameter, which averaged 25 pounds tenacity..

Jan 1, 1879

By James B. Graham, Earle E. Smith

The value of all minerals produced in the United States for the years 1930 to 1932 averaged $3,460,000,000 annually, according to Bureau of Mines reports. Of this amount, approximately $1,280,000,000 represents nonmetallic substances, such as petroleum, gas, sulfur and salt produced as fluids. Thus, about.37 per cent of the country's mineral wealth is procured through wells drilled in the earth, which require casing to keep them open throughout their life. Deep well drilling has increased greatly in the last few years. Several strings of casing have been set deeper than 9000 ft.—one, a string of 7?-in. O.D. casing, 10,301 ft. long, run in a well drilled by the Gulf Production Co. in West Texas, holds the record up to this time. These are longer strings than were contemplated when the American Petroleum Institute Specifications were adopted 10 years ago, therefore it is necessary to consider whether the present joint standards are adequate for such strings, or for even longer strings that may be called for in the future. Petroleum engineers are asking: Is there a possibility that stronger joints can be designed without going to stronger and more costly steels than offered in present specifications? Without sacrificing too greatly the tensile properties of the joint, can its design be changed to allow more clearance in the open hole below the next larger string of casing, and thus avoid costly underreaming? What can manufacturers offer for drilling through heaving shale? Fundamentals of the Problem During the last few years considerable study has been given to casing joints and their limitations, and since attention must be given to this subject by those who will be required to drill deeper holes, it is timely to review the fundamentals of the problem. These will be recognized generally as the following: 1. No threaded joint can be stronger than the area of metal under the root of the first perfect thread, and this area must be large enough

Jan 1, 1935

By V. F. Parry, S. P. Burke

The presence of gas in coal mines necessitates the use of costly ventilation arrangements and the use of expensive mining methods. On the other hand, the gas itself in many instances is of considerable intrinsic value, and its separate recovery might conceivably be a profitable undertaking. This paper is concerned with a study of the movement of gas in coal strata with the object of determining the laws governing gas movement and thus making at least a preliminary step toward the solution of the more practical problem of its control or recovery. Naturally, so important a subject has received much attention from scientists and engineers. In most cases, however, the studies have been concerned with the origin1$, the amount" the composition3 and the method of retention4 of the gas in coal; or, from the more practical side, have been concerned with the phenonlena and conditions associated with outbursts5 or explosions and their control. Numerous studies also have been made of the permeability of coal to gas" of gas pressures measured in coal seams, etc. The authors are unaware, however, of any attempt to present a consistent or complete picture of the laws governing the movement of gas through the coal. Study in West Virginia A recent study conducted at this University7 gives the first presentation of the distribution of pressures in a small section of a coal seam. Holes were drilled into the coal rib to various depths and at various distances from the coal face. The location selected for study was as remote as possible from disturbing influences of mining operations, faults, "wants," etc. The pipes extending into the coal that were used to determine pressures were grouted into the borehole for the entire depth of the hole, and great precaution was taken to insure accurate pressure readings. A map of the geology of the region, a map of the probable boundary and extent of the coal seam, a current map of the mine and a

Jan 1, 1936

By C. D Looker

Common salt is mentioned in the most ancient writings as an important article of diet. It is fairly certain that it was used by men and animals long before the dawn of civilization. Its presence in natural springs has often been the determining factor in colonization; wars have been fought for possession of salt deposits; trade routes have been established expressly for the purpose of traffic in salt. Naturally this led men into adventures and discoveries that altered history and advanced civilization. In the early days the uses for salt were few and the methods of manufacture were crude and the purity low when compared to salt of the present day. Then the salt came largely from springs, shallow wells or the ocean, while today deep wells must be drilled to the natural brines or beds of rock salt and spacious shafts sunk so that the ancient deposits may be made to yield their supply of stored mineral. Mining and Purification The quantity of available salt seems inexhaustible. It occurs in practically every country of the globe. About 20 million tons is produced and consumed annually in the world. Of this amount about 7 million tons is produced in the United States; 13/4 million tons of rock salt, 2 1/4 million tons as evaporated salt and 31/2 million tons in brine used in the chemical industry. Mined rock salt is used in its natural state without purification. It is classified for the trade by crushing and screening. The average purity of rock salt mined in the United States is about 98.3 per cent pure sodium chloride1. The usual impurities are gypsiferous shale, anhydrite and silica, with traces of potassium, magnesium and calcium compounds. Refined or evaporated salt is made by crystallizing the salt from brine in open pans or vacuum pans. A comparatively small amount of salt is made from ocean water or the brines of inland lakes or seas, sometimes by solar evaporation. By far the larger amount of brine is obtained by drill-

Jan 1, 1938

By V. F. Parry, S. P. Burke

The presence of gas in coal mines necessitates the use of costly ventilation arrangements and the use of expensive mining methods. On the other hand, the gas itself in many instances is of considerable intrinsic value, and its separate recovery might conceivably be a profitable undertaking. This paper is concerned with a study of the movement of gas in coal strata with the object of determining the laws governing gas movement and thus making at least a preliminary step toward the solution of the more practical problem of its control or recovery. Naturally, so important a subject has received much attention from scientists and engineers. In most cases, however, the studies have been concerned with the origin1$, the amount" the composition3 and the method of retention4 of the gas in coal; or, from the more practical side, have been concerned with the phenonlena and conditions associated with outbursts5 or explosions and their control. Numerous studies also have been made of the permeability of coal to gas" of gas pressures measured in coal seams, etc. The authors are unaware, however, of any attempt to present a consistent or complete picture of the laws governing the movement of gas through the coal. Study in West Virginia A recent study conducted at this University7 gives the first presentation of the distribution of pressures in a small section of a coal seam. Holes were drilled into the coal rib to various depths and at various distances from the coal face. The location selected for study was as remote as possible from disturbing influences of mining operations, faults, "wants," etc. The pipes extending into the coal that were used to determine pressures were grouted into the borehole for the entire depth of the hole, and great precaution was taken to insure accurate pressure readings. A map of the geology of the region, a map of the probable boundary and extent of the coal seam, a current map of the mine and a

Jan 1, 1936