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By G. W. Imholz

The effect of new discoveries and development of other pools recently discovered is reflected in the increase in production from 586,000 bbl. during 1940 to 758,000 bbl. during 1941 in Coleman County. The States Oil Company's No. I Hudson, Coleman County, was the discovery well of the Silver field, with a total depth of 3540 ft.; initial production, 10,000,000 cu. ft. of dry gas and 60 bbl. of oil per day from the Gray sand, topped at 3482 ft. The first well drilled in the new Jim Ned field was the Merry Bros. and Perini No. I Greer, also in Coleman County. It had a total depth of 3937 ft. and an initial production of 152 bbl. of 42" gravity oil in 6 hr., through I-in. choke, from Gray sand encountered from 3909 to 3937 feet. J. E. Farrell's No. I Rose, Haskell County, was a new discovery, around which no additional wells have been drilled. Total depth was 3002 ft., plugged back to 2780 ft. to test an oil sand encountered from 2663 to 2685 ft., which when perforated with 76 shots at that depth was good for 85 bbl. of 40" gravity oil. In Fisher County, General Crude drilled its No. 12 Flanagan to a total depth of 6746 ft. After plugging back to 4578 ft. to test a sand encountered from 4515 to 4528 ft. it was abandoned as a dry hole. The top of the Ellenburger was reported as 6094 feet. Interest in Jones County continued unabated, largely through the development of the Wimberly pool in the southern part of the county, where five Cisco sands are producing. At present the pool has been defined on the south and the southwest. The structure has 170 ft. of closure; the lower limestone pays producing on top of the structure and the fist pay encountered, the Akard sand, producing on the flanks of the structure. Five deep wells were drilled in Stonewall County (H. and T.C. survey)—the Shell Oil Company's No. I-A Patterson, in block D, with a total depth of 6827 ft., dry and abandoned; the Shell Oil Company's No. I Rutherford, block I, with a total depth of 6239 ft., dry and abandoned; the Leader Oil Company's No. I Bilberry, block D, with a total depth of 5700 ft., dry and abandoned; Forest Development Company's No. 2 Boyd, block D, with a total depth of 4753 ft., dry and abandoned; and the Hunter et al. No. I Boyd, block D, total depth 4757 ft., dry and abandoned. J. E. Farrell drilled his No. I Tipton south of a well that produced from a Strawn sand for some time, to a total depth of 5202 ft., where it was abandoned. The well is in the southwest corner of sec. 43, block 19, T. and P. survey, Nolan County.

Jan 1, 1942

By S. M. Marshall

FOR a number of years European investigators have used laboratory methods of predicting the probable strength of coke made from coal, and recently several investigators in the United States have reported the use of various tests for this purpose. There is at present no method accepted as standard, however, nor is there even agreement as to the general type of test that should be used. Furthermore, because the details of most of the tests have not been worked out carefully, one investigator can not hope to duplicate the work of another. The extension of coke manufacture to new localities in the United States, and the increasing need for cokes of exceptional qualities made from the most economical mixtures, made it desirable to have some simple laboratory test which will determine whether given coals, alone or blended with other coals, are more satisfactory from the standpoint of coke strength than others of different cost. The work described herein has resulted in the development of a simple laboratory test which, it is believed, can be generally adopted in coal laboratories, and which will give concordant results even though performed by different investigators in different laboratories. The general method of predicting whether a coal or a mixture of coals will produce a strong coke, resistant to crushing and shattering, has been to correlate the known strengths of the cokes produced in commercial ovens with some measurable constituent or with some property of the coals, and then to use the relationship so found for forming an estimate of the coking strengths of coals unknown. Several such correlations have utilized the percentages of the various ultimate constituents of coal, such as the oxygen content and the hydrogen-oxygen ratio;(39)§ other correlations have involved the proportion of a, (3 and y compounds, (17'21,30 or of "oil and solid bitumens."(16,30) Also a relationship has been traced between the coking properties of coal and the rate of change of the resistance offered to the flow of an inert gas by fine particles of the coal while being slowly heated. (11,17b) But the most general corre-

Jan 1, 1929

By Albert R. Ledoux

Discussion of the Paper of Albert R. Ledoux, read at the Atlantic City Meeting, February, 1904. ARTHUR JARMAN, Sydney, New South Wales, Australia' (communication to the Secretary*): Some remarks upon. Dr. Ledoux's interesting paper from one who has not visited America may, I hope, be of interest to members. It appears to me that there is considerable difference between the training of the American and of the British mining engineer. Not that the subjects are different, but rather in the way in which they are handled, the illustrations being, as far as possible, mining in character. Colloquial instruction is unknown in English curricula, but could be introduced with advantage. Students here assure me that an hour of conversation is of tar more use to them than an hour of the best lecturing. In England a school-year of 6 or 7 months would be considered very short indeed; but Americans do not consider it so, for the reason that the rest of the year is mostly spent in acquiring practical acquaintance with their subjects in works or in the field, and the shorter courses, when coupled with this large amount of outside expe¬rience, produce an essentially practical-minded engineer, who is also more of a business man; whereas the English system, though excellent from a scholastic point of view, produces the theoretical rather than the practical man. British schools are waking up, however, and the practical aspect of the engineer's training is receiving greater consideration. Once launched upon his career, the American engineer is immediately called upon to exercise his self-reliance and ingenuity, if he is to retain the confidence of his employers; but what can we say of English directors? In how many cases is the engineer allowed to guide the destinies of his company? Witness several recent cases of gross waste of money upon unsuitable plants, and the perpetuation of prehistoric methods of

Mar 1, 1905

By C. H. Frick

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

Jan 1, 1949

By C. H. Frick

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

Jan 1, 1946

By Henry M. Howe, W. P. Barba

When this country went into the war, but two concerns, The Bethlehem Steel Co. and The Midvale Steel and Ordnance Co., knew how to make steel fit for great cannons and at these concerns there were relatively few men who knew the whole art. Fortunately, certain of these men put their knowledge at the service of the Government, and proceeded to instruct the metallurgists at the arsenals and at various steel works. Doctor Howe, then chairman of the Engineering Division of the National Research Council, suggested that this work might be facilitated, and the number of effective gun-steel makers thereby increased, if a detailed description of the best practice could be written, giving the reasons for the various steps, and issued with the endorsement of a committee composed of those who were evidently the most competent authorities. It was thought that something would be gained by clarification of the subject, and something by the eminent authority of the members of the committee. To that end, the Engineering Division appointed a committee, consisting of the gentlemen whose names follow, to mention on1y those who retained their connection with it. At this time there were serious difficulties in the manufacture, for the Government. of aircraft and high-speed engine crankshafts, of certain ordnance forgings, and of shells for both the Army and Navy. This Committee was asked to study and report upon these, with a view to betterment of practice. There were indications that the source of some of the difficulties went back to the melting of the steel and the production of the ingot. Hence, the committee first studied steel melting and ingot production, in order to guide the wartime manufacturers to an even larger percentage of useful production from the steel initially melted. Committee on Steel Ingots W. P. Barba, chairman, Ordnance Dept., U. S. A. (formerly Vice Pres. & Gen. Mgr., Midvale Steel Co., Philadelphia). George K. Burgess, Chief of Division of Metallurgy, U. S. Bureau of Standards, Washington, D. C. Henry M. Howe, Then Chairman Engineering Division, National Research Council.

Jan 1, 1922

By W. P. Barba, Henry M. Howe

When this country went into the war, but two concerns, The Bethlehem Steel Co. and The Midvale Steel and Ordnance Co., knew how to make steel fit for great cannons and at these concerns there were relatively few men who knew the whole art. Fortunately, certain of these men put their knowledge at the service of the Government, and proceeded to instruct the metallurgists at the arsenals and at various steel works. Doctor Howe, then chairman of the Engineering Division of the National Research Council, suggested that this work might be facilitated, and the number of effective gun-steel makers thereby increased, if a detailed description of the best practice could be written, giving the reasons for the various steps, and issued with the endorsement of a committee composed of those who were evidently the most competent authorities. It was thought that something would be gained by clarification of the subject, and something by the eminent authority of the members of the committee. To that end, the Engineering Division appointed a committee, consisting of the gentlemen whose names follow, to mention on1y those who retained their connection with it. At this time there were serious difficulties in the manufacture, for the Government. of aircraft and high-speed engine crankshafts, of certain ordnance forgings, and of shells for both the Army and Navy. This Committee was asked to study and report upon these, with a view to betterment of practice. There were indications that the source of some of the difficulties went back to the melting of the steel and the production of the ingot. Hence, the committee first studied steel melting and ingot production, in order to guide the wartime manufacturers to an even larger percentage of useful production from the steel initially melted. Committee on Steel Ingots W. P. Barba, chairman, Ordnance Dept., U. S. A. (formerly Vice Pres. & Gen. Mgr., Midvale Steel Co., Philadelphia). George K. Burgess, Chief of Division of Metallurgy, U. S. Bureau of Standards, Washington, D. C. Henry M. Howe, Then Chairman Engineering Division, National Research Council.

Jan 1, 1922

By M. L. Samuels

DURING the period from 1910 to 1920, there was a lively interest in the subject of grain growth and many papers were published, followed by interesting discussions. Questions dealing with the fundamentals of grain growth-why and how it occurs-were treated in papers by Howe,1 Jeffries,2 Sauveur,3 Chappell,4 Beilby,5 Mathewson and Phillips,6 McAdam,7 Carpenter and Elam,8 Stead and Carpenter,9 Ruder,10 as well as others. Since that decade, much indeed has been done regarding the practical control of grain size, and it is now possible to order material having a size specified in the American Society for Testing Materials classification. Also, one hears the term "spliced boundaries" used in connection with certain tungsten lamp filaments" wherein it is important to prevent "sagging" between consecutive turns of the helix." This practical use of a certain knowledge as to the things that influence or even control grain growth should not be taken as an indication that the subject has been thoroughly explored and that nothing more can be learned from fundamental studies. It is with this thought in mind that a report of some observations and experiments on abnormal grain growth is believed justified. Abnormal grain growth is met with in heat-treating high-carbon steels in the austenitic range,13 in the hardening treatments of high-speed steels, 14.11 and in the low-temperature annealing of strained low-carbon steels as in sheet and wire material. Entirely aside from these instances of exaggerated grain growth, which some might consider as freakish, it is thought that abnormal growth is simply a case where the growth forces and the forces tending to prevent growth are almost, but not quite, evenly balanced. Information relative to grain-growth characteristics in general may be obtained from a study of abnormal growth conditions, which may be looked upon as vantage points. Reflection will show at once that if growth forces are great in comparison to inertia or resistance to growth, many crystals start to grow and, for that reason, none becomes very large, whereas if inertia is predominant no growth at all takes place. Under conditions in which

Jan 1, 1938

By Edward Keller

(Canal Zone Meeting, November, 1910.) UNDER the title, Labor-Saving Appliances in the Works-Laboratory, I published a paper1 in which was described how multi-manipulations, in a works-laboratory, and in the furnace-room of an assay-laboratory, can be condensed into single manipulations by applying the proper mechanical devices. For example, I now deposit in, or withdraw from, a muffle a set of 48 cupels as one unit. The front row. (8) of these. are blanks or heaters; the other 40, when they have attained the proper temperature in the muffle, are charged simultaneously with the 40 lead-buttons. Three manipulations here accomplish an operation which by the generally customary method requires 136, and this number is only limited by the size of muffle and cupels. This operation is an enlargement of what I have already described in my former paper, and Fig. I shows the improved implements. In the paper referred to I described a gold-silver bead parting-bath, which is the last of the devices used in regular sequence in practice. This bath was designated as being convenient, but was not a labor-saver properly. Fig. 2 of the present paper shows a new device. Instead of the original tray, there are now sectional holders for the test-tubes, each having a wooden handle on either end, so that the holders may be removed from the boiling bath, and the acid or water poured off from each set of tubes (in this case, 7) without waiting to cool. The tubes, held in place by clutches, as shown in Fig. 3, rest in holes in the base-strip, having a smaller diameter than the tubes. Each holder is stamped at either end with a number, so that the bath becomes further useful by permitting several men to use it at the same time without interference. Apart from the handles, the holders are made of sheet-copper. ' Trans., xxxvi., 3 to 18 (1906).

Aug 1, 1910

By C. W. Mac Gregor

THE observation of the flow layers, or Lüders' lines, produced in mild steel when it is stressed into the plastic range often provides considerable useful information for the study of the fundamental mechanism of the plastic flow of metals. It is a commonly observed fact that as soon as the upper yield point in a mild-steel tensile-test bar is passed, an unstable condition develops in the equilibrium, the load on the testing machine drops and if the surface of the bar contains a thin mill scale, the latter begins to flake off rapidly along certain "lines." These "lines" are in reality traces of wedge-shaped flow layers and are formed by the inter-section of the surface of slip and the surface of the bar. The average plane of the flow layer itself has been found by various experimenters to be inclined at an angle of approximately 45° to the axis of the test bar. In a body of more complicated shape stressed in possibly a different man-ner, the tangent planes to the flow layers at each point seem in many cases to be inclined at an angle of about 45° to the principal stress direc-tions at the point. As examples of the latter may be mentioned the logarithmic spirals obtained when a rivet hole is punched in a thin plate, or when a tube is subjected to internal pressure only, etc. Hence if the flow layers are observed from an experiment, the shear-stress trajectories -the curves indicating the directions of the maximum shearing stresses in the body-may then be approximately determined. Since the latter curves form an orthogonal family inclined at 45° to the principal stress directions, the family of principal stress trajectories, or the curves indicating the directions of the principal stresses, may be thus obtained. Although the discontinuous type of stress-strain curve at the yield point is commonly observed with test bars of mild steel, more recent experiments have shown that this is by no means the only material exhibiting this interesting phenomenon. A similar effect has been observed in zinc and cadmium crystals, by Becker and Orowan;1 in duralumin and other aluminum alloys, by Dawidenkow, 2 Elm,3 Fell, and others; in copper and copper-alloy crystals, by Elam;5 in brass by Elam;5 in brass wires by deForest;6 in higher carbon steels, tungsten steel, and

Jan 1, 1939

By Lyman Taylor, Alexander R. Troiano

STUDIES of the transformation of austenite at constant subcritical temperatures have been numerous since the work of Davenport and Bain.1 Considerable information has been obtained on low-alloy steels and on high-carbon alloys containing undissolved carbide or graphite at the austenitizing temperature. Little is known of the isothermal transformation of austenite containing in solution large amounts of both carbon and a single alloying element. In this investigation four steels containing one per cent carbon and with chromium in the range 3 to 9 per cent have been examined with the view to establishing the fundamental character of the isothermal reactions when all carbon and chromium are initially in solution in austenite. EXPERIMENTAL PROCEDURE Alloys The chemical compositions of the steels investigated are given in Table I. The 4 per cent Cr alloy is a commercial steel. The other steels were made by the Carpenter Steel Co. as 50-lb., induction-furnace heats and rolled to 5/8-in. round bars. Bars were softened at 650° to 700°C. before the specimens were cut. [ ] Metallographic Method Most of the lines on the transformation diagrams presented here have been placed on the basis of the microscopic examination of partially reacted specimens. Thees specimens were approximately ½ by ¼ by 1/8 in. in size. Specimens of the 9 per cent Cr steel were held 10 to 12 hr. at 1200° to I225°C. before quenching to the various subcritical temperatures. The other steels were held for 2 to 2 ½ hr. at 1200°C. before quenching. These treatments, carried out in an atmosphere of purified nitrogen, produced an austenite grain size larger than A.S.T.M. No. I, some grains being 1 to 2 mm. in diameter. There were a few undissolved carbide particles in some specimens of the 9 per cent Cr steel. It is believed, however, that any errors in the results due to incomplete solution of carbon and chromium in austenite are negligible; that is, austenite compositions may be considered as being those listed in Table I. X-ray Methods Constituents were identified and martensite axial ratios determined from Debye

Jan 1, 1945

By Aug. J. Jr. Bowie

(Read at the Wilkes-Barre Meeting, May, 1877.) Brief Outline of the General Topography of the Gold Regions of California. THE topographical features of California, as demonstrated by the explorations of the State Geological Survey, are found to be exceedingly simple. Three equidistant parallel lines can be used in conveying a general idea of the physical geography of Central California. A straight or " main axial line," whose course would be north 31° west, passing through the culminating peaks of the Sierra for a distance of five hundred miles, can be assumed as the eastern boundary of the State. A second parallel drawn fifty-five miles west of the " main axial line" will skirt the western base of the Sierra Nevada, along the edge of the foot-hills. A third parallel run equidistant from the second will represent "as nearly as possible the western base of the Coast Ranges." These parallel lines divide the State into three belts, namely, the Sierra, the Great Valley of California, and the Coast Ranges. " This arrangement of the physical features holds good for a length of four hundred miles in the direction of the main axial line, comprising almost the whole of the agricultural and the greater part of the mining districts."* The section of the country which is of immediate interest to the miner is the western slope of the Sierras. These mountains, rising in a short distance from the Sacramento plains to elevations of over seven thousand feet, with occasional peaks ten and twelve thousand feet high, are cut by numerous deep and precipitous gorges or capons, through which drains the immense watershed of the Sierra, supplying the main rivers of the State and ultimately emptying into the Pacific Ocean. Between these capons, ridges or divides are formed, on top of * See vol. i, p. 5, Geological Survey of California. J. D. Whitney, State Geologist.

Jan 1, 1878

By W. P. Sykes

In connection with a study of tungsten steels, Honda and Murakamil reported an investigation of the system iron-tungsten. This report included a tentative equilibrium diagram, photomicrographs of various alloys in the series, and qualitative measurements of hardness and magnetic properties. The present investigation originally had as its object the study of the hardness and tensile properties of a series of carbon-free iron-tungsten alloys. But, as the work progressed it became evident that the system possessed other features of interest, so the scope of the investigation was enlarged. Materials The iron powder used in preparing the alloys was obtained as follows : Iron oxalate was precipitated from a ferrous-sulfate solution by the addition of a solution of oxalic acid. This oxalate, after thorough washing, was ignited to iron oxide, which after reduction in hydrogen at about 1000" C. yielded iron powder containing but about 0.2 per cent. iron oxide and about 0.005 per cent. carbon. Tungsten metal in the form of powder, such as is used in the manufacture of filaments for incandescent lamps, was the other constituent. This material analyzed 99.8 per cent. tungsten and contained no carbon. The metal powders, in the desired proportions, were mixed by tumbling and formed, under pressure of 20 tons per sq. in., into rods 3/8 by 3/8 by 10 in. To form the alloys without contamination, sections of the pressed rods were placed on alundum slabs and heated in an alundum tube wound with a tungsten resistor and packed in heat-insulating material. While the resistor was heated, a stream of hydrogen was continually passed through both the tube and the case containing it. The tungsten winding on the tube, as well as the material heated within the tube, was thus protected from oxidation. Such a furnace will operate constantly for several days at temperatures up to 1500' C. and for shorter periods

Jan 1, 1926

By D. Harrington

ALTHOUGH statistical data are not at hand to justify definite statements as to progress in health, and safety in the mining and allied industries during 1935, it now appears probable that in both coal mining and in metal- mining the rate of accident occurrence as well as the absolute number of accidents will show slight increases for the year. Much: of the responsibility for this increase lies with the large number of relatively. small mines that have more or less recently come into existence, partly because of 'the lack of opportunity for work in the larger mines for large numbers of unemployed miners, and partly due to increased prices for some of the mineral products, especially gold. In general, the larger long-established nines show downward accident trends and this is decidedly encouraging as it shows that where mines are operated with real efficiency, mining can be done in relative safety.

Jan 1, 1936

By AIME AIME

IT its annual meeting on Oct. 21 and 22, the Engineers' Council for Professional Development announced the selection of J. P. H. Perry. vice-president of the Turner Construction Co. and prominent civil engineer of New York City as its new Chairman. He succeeds C. F. Scott, who becomes Chairman of its Committee on Professional Recognition. S. L. Tyler, Secretary of the American Institute of Chemical Engineers, succeeds A. B. Parsons as ECPD Secretary. R. E. Doherty is Vice-chairman. C. E. Davies remains as Assistant Secretary, as do R. L. Sackett as Chairman of the Committee on Student Selection and Guidance, O. W. Eshhach as Chairman of the Committee on Engineering Training, and Karl T. Compton as Chairman of the Committee on Engineering Schools.

Jan 1, 1938

Sykes, W. P.-Effect of Temperature, Deformation, Grain Size, and Rate of Loading on Mechanical Properties of Metals. Discussed by Zay Jeffries, W. H. Bassett, F. E. Carter 3 Evans, Geo. Watkin.-Alaskan Coal Fields. Discussed by P. N. Moore, H. H. Stoek, G. S. Rice, H. Emerson 4 Eavenson, Howard N.-Run-off and Mine Drainage. Discussed by J. R. Campbell, Andrew B. Crichton, J. B. Warriner, R. V. Norris, H. G. Moulton, H. B. Wright 7 Andrews, Allen, and Garcia, John A.-Skip Hoisting for Coal Mines. Discussed by R. V. Norris, Geo. S. Rice, H. N. Eavenson, E. A. Holbrook, Robert Obert, Andrews Allen, T. M. Chance 12 Rice, Geo. S.-Coal-pillar Drawing Methods in Europe. Discussed by Carl Scholz, D. Harrington; H. 1. Smith 16 Knapp, Arthur.-Modified Oil .well Depletion Curves. Discussed by Roswell H. Johnson 21 Alvey, Glenn H., and Alden W. Foster.-Barrel-day Values. Discussed by Roswell H. Johnson 22 Matteson, W. G.-Secondary Intrusive Origin of Gulf Coastal Plain Salt Domes. Discussed by Eugene Coste, E. W. Shaw, Joseph E. Pogue, F. G. Clapp, E. DeGoIyer, W. G. Matteson, H. W. Hixon, R. Van A. Mills 23 Reger, David B,-Carbon Ratio of Coals in West Virginia Oil Fields. Discussed by J. T. Singewald, Jr 33

Jan 5, 1921

POSITIONS VACANT (Under this heading will be published notes sent to the Secretary of the Institute by members or other persons.) Position open as assistant superintendent at a steel plant. Practical experience in the manufacture of crucible and open-hearth steel and heat treatment of steel and alloy steels required. This position offers an excellent future. No. 9. A company in Virginia desires a man with experience in Western mines to act as superintendent of its pyrite mine. No. 15. Position open as instructor at a University in Middle West to teach the mechanical side of mining, such as hoisting, haulage, drilling, and mine surveying. Salary, $1,500 to $1,800. No. 16. Experienced amalgamator wanted at a mill in Ivory Coast, Africa. An American speaking French preferred. No. 18.

Jan 5, 1914

Mine Transitman.-Engineer, about 30 years of age, experienced in coal mine underground surveys. Must be good draftsman and possess sufficient personality to get results from the men. Location, Illinois. No. R 419. Coal Mining Engineer: Coal mining engineer of proved ability for position of manager f high-grade bituminous coal property. Location, Canada. No. R 427. Chemist or Metallurgical Engineer.-Chemist or metallurgical engineer for special library work. Man with scientific training with the ability and education -of a young instructor in a university. Duties would consist of working out a new method of indexing scientific information, more particularly in obtaining information for use of a Committee on the Heat Treatment f Steel. Location, Washington, D. C. No. R 470. Topographical Draftsman.-Civil engineering training and topographical and surveying experience. Unmarried man, under 40 years of age. Knowledge of Spanish not necessary. Discharged army or navy man preferred. Location, oil fields, Mexico. Salary, $5 per day, living and traveling expenses. No. R 483. Mechanical Draftsman.-Engineering training, familiarity with drawings of pumps, piping, etc., need not necessarily be a designer. Unmarried man, under 40 years of age. Discharged army or navy man preferred. Location, Mexico. Salary $5 per day with living and traveling expenses. No. R 484. Engineer Translator.-Engineer of Portuguese nationality who has received his technical training abroad, and has been filling engineering positions in this country, to translate material for catalogs of an engineering character. No. R 486.

Jan 5, 1919

A shrinkage stope is an overhand stope in which the broken ore accumulates until the stope is completed to, or near, the level above. As broken ore generally occupies at least 60 per cent. more space than ore in place, about a third of this must be drawn out as the stope advances to leave a working space under the back. The ore remaining supports the miners and gives temporary support to walls, and is all withdrawn when the stope is finished. The shrinkage-stope method is applicable to steep-dipping deposits of strong ore with strong walls. It may be applied to narrow or wide veins, and is simple and cheap. Five examples, which include important and varied types of deposits, are given: namely, Kennecott, Homestake, Jarbidge district, Mogollon district, and Cripple Creek district.

Jan 1, 1925

By E. P., Mathewson

THE most important improvements in copper metallurgy today are the advances in the art of leaching and electrical precipitation of copper from solution; the development of flotation processes; improvements in crushing and pulverizing machinery; the enlarged units of both reverberatory and .blast furnaces, together with the application of pulverized coal to both styles .of furnaces; the enlargement of' units for converting copper and the improving of the mechanical design of converter shells and equipment; the electrical precipitation of flue dust and fume from escaping gases.

Jan 1, 1921