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By Ernest Stütz

(New York Meeting, October, 1913.) THE problem of increasing blast-furnace efficiency through diminution of flue-dust production while operating with burdens consisting largely of fine ores has of recent years attracted the attention of metallurgists, whether directly or indirectly interested in the economies of iron smelting, and the various methods evolved from theory or practice have been. submitted to wide discussion. After the very thorough and, at that time, exhaustive view of the whole subject, which was afforded to the industry by the meeting of this Institute in February, 1912, the subject was again taken up at the meeting of the Verein deutscher Eisenhüttenleute at Düsseldorf in December, 1912. While American and German conditions are not entirely identical, it may be of interest to give here the words of the gentleman summing up the discussion at the Düsseldorf meeting : ?The chief advantage offered by the use of briquettes lies in the fact that disturbances in the furnace, caused mostly by the presence of fine ores in the burden, are avoided, and that blast pressure can be considerably reduced. The resulting economies cannot be overrated, as, with lower blast consumption per ton of product, the installation will be able to take care of increased production. In consequence of lower pressure and speed of blast, heat is more efficiently utilized,, flue gas temperature is lowered, and coke particles are less liable to be carried along with the flue dust, of which considerably less is produced. Finally, by increased regularity of operation and higher temperature in the lower parts of the furnace, the quality of the product is improved. The question of briquetting iron ores has grown to be one of the most important in the iron industry, and it is not any more a question of what is the cost 'of briquetting a ton of ore, but what, in. using ore briquettes, is the cost, of: production of a ton of iron."

Jan 7, 1913

By Hamilton Bell, E. W. Webb

RepressuRIng, or gas drive, was first tried in the Seal Beach oil field during the fall of 1927, and was carried on until the spring of 1928. This experiment in the Upper or Bixby zone was highly successful in proving the feasibility of compressing gas to high pressures and also showed great increases in production. The project was discontinued because there were not enough wells to protect the property lines. In the development of the second or Selover zone, many more wells were drilled and after 2½ years of production the gas was depleted so that all producing wells in the zone were either pumping or on gas-lift. Edge-wat'er encroachment and the deepening of wells on neighboring properties to a third zone practically isolated the lease, so that during the spring of 1929 it was considered feasible to repressure the Selover zone on the Bixby lease of the Continental Oil Co. (Marland). As shown on Fig. 1, the main Seal Beach structure is an elongated dome with a northwest-southeast trend, and the north flank is cut by a fault nearly parallel to the axis of the structure. Bixby well No. 24 was chosen for the injection well on account of its location, as it is backed up by the fault and is surrounded by wells that protect the property lines. The results of the test made in the Bixby zone indicated that an injection well on the flanks of the structure would drive oil quickly to up-structure wells but would have a tendency to cause by-passing, while the drive to down-structure wells would be slower but more evenly distributed. Preferably the injection well would have been located on top of the dome but property divisions made this inadvisable. Well 24 had been completed in November, 1928, but on account of gas depletion the well failed to flow naturally. On gas-lift the well had an initial production of 1000 bbl. of oil with 30 per cent. emulsion. This well is 4825 ft, deep, penetrating 200 ft. of oil-bearing formation. At the time the well was prepared

Jan 1, 1930

The Atlanta Mine is located in east central Nevada, in Lincoln County, 116 km (72 miles) south of Ely and 80 km (50 miles) northeast of the old mining town of Pioche. From this famous district, high-grade copper ore was mined and shipped to a smelter in Wales in the 1850s; an early day lead blast furnace was also in operation. The Standard Slag Company began operations in May 1975 on the well known Atlanta Mine, which was operated by Roy Hardy in the 1930s. The mill is currently processing 450 mtpd (500 stpd) of gold-silver bearing ore. Mining by open pit is in a brecciated zone occurring between limestone-dolomites on the foot wall and tertiary rhyolites on the hanging wall. The quartz breccia is considered among the most abrasive in the world - shovel teeth must be replaced every week. Stripping ratio is 3.9 to 1.0. Because of the hard abrasive ore, the crushing plant consists of four units: two jaw crushers in series, one Hydrocone, and one Gyradisc. Mine feed to the primary crusher is limited to 610 mm (24 in.) in size. The remaining crushers work in closed circuit with screens to produce a mill feed of 6 to 13 mm (0.25 and 0.50 in.). Hardness of the ore is demonstrated by the fact that the reversible liners of the primary jaw crusher had to be replaced in early 1978 after handling only 39,000 mt (44,000 st) at a cost of $0.095 per mt ($0.086 per st). Another example of the extreme abrasiveness of the breccia ore was the total cost per ton in 1977 for all wear parts in the comminution circuit, including screens and grinding media. This amounted to $2.84 per mt ($2.58 per st). The Atlanta grinding plant consists of three ball mills to grind the 7 mm (1 /4 in.) crushing plant product to 85 to 90% minus 150 microns (100 mesh). Feed rate to the primary Tricone mill is determined by maintaining a cyclone overflow at 28 to 38% solids, which controls the grind mentioned above. A mixture of 90 and 65 mm (3.5 and 2.5 in. ) balls are charged to this primary mill. Both the secondary mills are charged with 50 mm (2 in ) balls. Total ball consumption is 2 kg per mt (4 lb per st). All three ball mills use rubber liners. Primary mill cyclone underflows are fed to the secondary mills close circuited with the same cyclones.

Jan 1, 1981

By Edgar L. Newhouse

The lead smeltery at East Helena, Mont., controlled by the American Smelting & Refining Co. since 1899, has been in continuous operation for the past 25 years. Most of the old smelting and roasting practices have been superseded by newer and more modern methods, but on account of the difficulties involved in changing the original construction, some of the methods in use of handling materials are not the most modern. This plant, however, is particularly interesting as being one of the few essentially lead smelteries in the United States. At Federal, Ill., Collins-ville, Herculaneum, and possibly other places, similar work is being done, but it is doubtful whether any of them produces as much lead as the East Helena plant, whose monthly production averages 6,500 tons. The situation, 5 miles east of Helena, is convenient to both the Great Northern and Northern Pacific railroads, while the electric power is obtained from Canyon Ferry, 12 miles east on the Missouri river. Local quarries supply the requisite amount of lime rock, which the contracts require to be crushed to 5 in. Of the 450 men on the monthly pay roll, a census showed 200 Austrians, 110 Americans, and 30 Italians, the balance being made up of miscellaneous nationalities. The ore supply is mainly derived from the Coeur d'Alene mines in Idaho, and consists of crude ore, coarse and fine concentrates, middlings, and slimes. About one-half of the total output of the Coeur d'Alene camp is sent to East Helena. An average analysis of these ores gives approximately 40 per cent. lead and 11 per cent. sulphur. Local shipments, varying from month to month, are mostly highly siliceous gold and silver ores carrying little lead. Small shippers, leasers of old mines, and prospectors are very numerous throughout Montana, and it is the policy of the company to encourage these men by every possible means, including the free sampling and analysis of their ores and aid in the development of their mines and prospects, whenever their results show promise.

Jan 1, 1915

By Charles Legrand

In many iron, coal and copper mines where large tonnages are known before starting operation and proper provisions can be made, the problems of electric traction by trolley locomotives are not very different from those of surface plants. In such installations the gauge of the track, the radius of curves, and the clearances, both vertical and horizontal, can be made to suit the conditions of the traffic. It is more difficult to install electric traction in mines which were started with hand tramming and where no consideration was given to the possibility of mechanical traction being used. The writer having had some experience in the installation of electric traction in copper mines, the following remarks apply more particularly to these mines. With the gauge of track usually 18 or 20 in., the weight limit of locomotives obtainable from manufacturers in this country varies from 3 to 6 tons. The full-load speed varies from 49 to 6 miles per hour. These locomotives, being made to run on very small radius curves, have a short wheel base and a long overhang from axle to coupling, which necessitates a coupling' with a good deal of lateral motion to avoid derailing the cars on sharp curves, especially if couplings are of the standard railroad automatic type. Although 3-ton locomotives will run on 12- or 16-lb. rails, it has been found more satisfactory to use 25-lb. rails, as the track keeps in much better shape, it is easier to maintain the bonding in good order, and fewer derailments from dirt on the track occur with the larger rails. Where 6-ton locomotives are used the 25-lb. rails are satisfactory, but 40-lb. rails have proved cheaper where the traffic is heavy and the ground is soft, as the track maintenance is considerably lower with the heavy rails. The locomotives will run on 15-ft. radius curves, but on through runs it is advisable not to go below 40-ft. radius. The voltage used should not exceed 250 to 275 volts, and the trolley wire should be protected, to prevent accidental contacts, in front of chutes and at all points where it is low. With the air lacking somewhat in oxygen and the heat and high humidity prevalent in many mines, this

Jan 1, 1915

By R. D. Carnahan, J. E. White

ThE use of strain gages in the measurement of microplastic behavior of materials is well-known.'-3 Recently it has been suggested that similar techniques might be useful for determining stress relaation. It is the purpose of this report to comment on the use of strain gages in the measurement of strains in the vicinity of 10"6. We will also discuss observations of an anomalous anelastic behavior apparently associated with small temperature changes, which accompanies the unload portion of a load-unload microstrain test. The key to successful strain determinations at levels below 1 pin. per in. is a good gage-mounting technique and either precise ambient temperature control or a set of matched temperature-compensated gages. The importance of good mounting cannot be overemphasized, for example, as in the use of Eastman 910 contact cement. If the cement layer is not sufficiently thin and properly hardened, it is possible to observe anomalous negative stresses when small loads are removed, which relax back to zero in an orderly way with time. Such anomalous behavior, thought to be due to gage bonding, has been reported in microstrain experiments by Thomas and verbach' who observed a negative strain of -3 X lo-' upon unloading. This kind of behavior severely limits the over-all strain sensitivity which can be achieved in such tests. The relaxation of a small positive strain subsequent to unloading in a load-unload experiment is quite normal, however, and is to be expected. The occurrence of an apparent negative strain is also encountered in those instances where the elasticity of the bonding cement is exceeded—for example 0.5 pct or 5000 pin. for cured Eastman 910. An elastic strain of this magnitude can be encountered during load-unload type testing particularly in higher-strength materials (-150,000 yield strength). During the course of microplasticity studies on pure nickel and nickel alloys,' the authors have made the following observation. In a four-point bending test, two active gages are mounted one on each side of the beam as arms R1 and R z of a conventional strain-gage bridge circuit shown in Fig. l(a). This technique provides two advantages: the sensitivity is doubled because R1 and Rz experience opposite strains and temperature compensation is provided automatically because any ambient temperature change would cause both gages to see a strain of like sign whose signals would cancel in the circuit.

Jan 1, 1964

By Marcel Schlumberger

The electrical methods for surface-prospecting have been well developed in the last 20 years. The method involves, in the classic form, the sending of an electrical current into the soil, by means of two electrodes A and B, and studying the potential distribution at the surface, by measuring the difference of potential between pairs of points such as M and N. The points M and N are usually placed on a line between, and equidistant from, A and B. By increasing the distance AB, the current sent into the Earth, and likewise the distribution of surface-potentials, become influenced by regions of greater and greater depth below the surface. By varying the form and dimensions of the electrode-arrangements AMNB, called a "quadripole," one may make valuable deductions concerning the nature or thickness of beds, if one knows the electrical properties of these beds. On the other hand, if the form and dimensions of the electrodes AMNB remain fixed, the depth of penetration of currents in the Earth remains, so to speak, almost constant, although it tends to increase where the subsoil is more conductive, and conversely. Therefore, if one moves the constant-dimension quadripole over all the terrain to be Investigated, one achieves approximately a horizontal exploration. This permits a study of tilted beds or faulted horizon-tal beds. When the particular problem becomes deep, of the order of 2000 meters, or more, it is ne-cessary to Increase the distance between the current-sources AB to a length such that the work 'comes very troublesome, especially if the region is wooded. At the same time, the separation the points M and N must be likewise great (for example, one km) in order to obtain differences potential which are not too small; the measurement of potential differences across MN is then difficult because of the presence of parasitic potentials, due to a flow of telluric currents in fourth, and the order of greatness of these currents may exceed the quantities to be measured.

Jan 1, 1940

THERE have always been in this world men of such keen intelligence that with their discourse they have been capable of infinite and various inventions that are as beneficial as they are simultaneously harmful to the human body. Wherefore, from day to day, we see unfolded before our eyes some of these that greatly astound our minds, and we remain so stupefied that when-we think of them we are not able to control our faculties for some time, both from considering by what necessity or purpose these men were goaded, as well as from contemplating the profound subtlety of their discoveries, which, in truth, are such that they are awarded the greatest commendation by noble minds. By following their counsels and with their aid, there have been* some astute and lever captains who have had certain pots or balls of earthenware carried by their infantry, expressly filled with compositions of powder or other unctuous liquors disposed to ignite easily. When they meet the enemy in battle and come up close to them, they try to strike vigorously with these in the first assault in an effort to throw them into disorder and to make them give way by breaking them up and drawing them out of formation. The smoke is harmful, but the fire very much more so. These are made in this way. Take the number of vessels that you have to make-it does not matter whether they are raw or baked as long as they are well freed from the moisture of the clay-and fill them a little more than half full with coarse gunpowder which has mixed in it pounded Grecian pitch and at least a third of crushed sulphur. Then pour in a covering a dito thick of strained pig fat mixed with powder. This keeps it from falling out when it is thrown and keeps the fire slower until it reaches the enemy. When this has been made, open up the pig fat a little at one side when you wish to throw it and put in a little fuse or a little good powder and apply fire, holding it in your hand until you see that the fire has taken hold well. Then throw it, choosing your time. A liquid composition is also made in a kettle in which are put pork fat, petroleum oil, oil of sulphur, live sulphur, [163] doubly refined saltpeter,

Jan 1, 1942

By W. H. Eardley

IT IS increasingly evident that the excellence of blast-furnace operation to a great extent depends upon the preparation of the products fed into the furnace. The preparation of these products is carried on largely in the roasting and sintering departments. Prior to the building of flotation plants in Utah and other western states for the treatment of lead-zinc ores, the gravity concentrates received at the Midvale smelter amounted to about 4000 tons per month, containing 24 per cent. lead and 10 or 11 per cent. zinc. This product was about 20 mesh-that is, 45 per cent. of it would be plus 20 mesh and the balance minus 20 mesh. About 1000 tons of pyrite per month, containing 5 per cent. lead and 10 per cent. zinc, was also received. These products were sent to the multiple-hearth roasters for calcining, after which they were sent to the Dwight-Lloyd machines for sintering with other ores. The sintering charge passed over the machines but once. The first flotation products received consisted of a wet, sticky, muddy mass, containing a large amount of moisture, up to 19 or 20 per cent., and it was almost impossible to feed .them with any degree of regularity, if at all, through our standard feeders; but the amount of flotation product received during the first year or so was relatively small and it virtually lost its identity by being mixed with a large amount of jig and table concentrates. As the quantity of flotation products increased, more efficient filtering was accomplished and the moisture greatly reduced. FLOTATION PRODUCTS RECEIVED At the present time the Midvale plant receives about 4300 tons per month of flotation product running 60 per cent. lead and 4.5 per cent. zinc, 85 per cent. of which is minus 200 mesh and contains about 8 per cent. moisture; and 4000 tons per month of pyrite of similar fineness, running about 2 per cent. lead and 3.5 per cent. zinc, containing about 10 per cent. moisture. The lower moisture greatly reduces the difficulties of handling, making it possible to run a 100 per cent. flotation feed on a multiple-hearth furnace without serious mechanical troubles. The calcine, however, would contain-nodules and balls of unroasted concentrates, sulfur elimination

Jan 1, 1928

By Paul Bechtner

THE name bentonite formerly was applied solely to a peculiar clay occurring in Wyoming and South Dakota, which was distinguished from other clays by its unctuous feel when wet and the property of swelling in water. In the last decade scientific studies of clay have recognized that bentonite is composed mainly of the clay mineral montmorillonite and the name bentonite has been extended to cover the entire family of clays that have montmorillonite as their chief constituent. Montmorillonite has the chemical formula of A1203-4Si0-xH2O, With Fe203 and MgO replacing part of the A1203. The montmorillonite crystal is an Si-Al-Si clay mineral, being formed of two silicon-oxygen sheets with an aluminum-oxygen sheet sandwiched between them. In contrast, kaolinite-the chief clay mineral of most clays other than bentonite-is Si-Al, one silica and one alumina sheet. The unit crystal of montmorillonite is much thinner than that of kaolinite, with greater surface area. These differences in crystal structure patterns are leading factors in the dissimilar properties and commercial uses of bentonite compared with other clays. Mineralogically, bentonites are 85 to 90 pct montmorillonite with fragments of feldspar, gypsum, calcium carbonate, quartz and traces of other minerals. They vary in color; the widely used Wyoming type is creamy white when dry and a light shade of tan when wet; the low-swelling bentonites of the southern United States and elsewhere are found in many shades of gray, blue, yellow, red, and brown. Pure white bentonites are rarer and generally of the medium or low-swelling type, though there are a few exceptions to that general rule. PROPERTIES Bentonites may be divided into two general classes: (1) those that adsorb large quantities of water, "swelling" greatly in the process, and that remain in suspension in thin water dispersions; (2) those that adsorb only slightly more water than ordinary plastic clays or fuller's earths, do not swell noticeably, and settle rapidly in thin water dispersions. Another distinction is that some varieties of the No. 2 type

Jan 1, 1949

NAME AND OBJECT. SEC. 1. This Institute is incorporated under the Membership Corporation Law of the State of New York ; its corporate name is AMERICAN INSTITUTE OF MINING ENGINEERS; and its objects are such as are stated in its Certificate of Incorporation. ARTICLE II. MEMBERS. SEC. 1. The membership of the Institute shall comprise four classes, namely (1) Members ; (2) Honorary Members , (3) Associates , and (4) Honorary Associates Only Members and Associates residing within the United States of America, Republic of Mexico and Dominion of Canada shall be entitled to vote at the meetings of the Institute. SEC. 2 All Members, Honorary Members, Associates and Honorary Associates of the American Institute of Mining Engineers as the same existed on the day of the incorporation of this Institute, are Members, Honorary Members, Associates and Honorary Associates, respectively, of this Corporation SEC. 3. The following classes of persons shall be eligible for membership in the Institute, namely, as Members and Honorary Members, all professional mining engineers, geologists, metallurgists or chemists, and all persons practically engaged in mining, metallurgy or metallurgical engineering ; as Associates and Honorary Associates, all persons desirous of being connected with the Institute who, in the opinion of the Council, are suitable. SEC 4. Every candidate for election as a Member or Associate of the Institute must be proposed for election by at least three Members or Associates; must be approved by the Committee on Membership, as prescribed in the By-Laws ; and .must be elected by the Council. Not less than three-fourths of the votes cast shall be necessary to an election Every person so elected shall become a Member or Associate, as the case may be, upon payment of his first dues as herein-after prescribed Each candidate for Honorary Member or Honorary Associate, must be recommended by at least ten Members or Associates ; must be approved by the Council ; and must be elected by ballot at a meeting of the Board of Directors by the unanimous vote of all the Directors present ; provided, however, that the number of Honorary Members and Honorary Associates shall not at any time exceed twenty SEC. 5. If any person elected a Member or Associate does not, within sixty days after notice of his election, accept the same and pay his initiation fee and dues for the current year, his election may be cancelled at the discretion of the Council.

Jan 1, 1917

By A. Andreas

New Mexico retained its position in 1938 as the sixth largest oil-producing state, with a total production of 35,510,176 bbl. This was 2,875,598 bbl. less than the 1937 production of 38,485,774 bbl., or a decrease of 0.077 per cent, which was caused by the lack of pipe-line facilities and storage at the pipe-line terminals. The production for Lea County (excluding Maljamar) was 32,926,788 bbl.; for Eddy County (including Maljamar) was 2,225,411 bbl.; and for northwestern New Mexico (San Juan and McKinley Counties), 357,977 bbl. The average daily nonmarginal well allowable for Lea County on Jan. 1, 1938, was 65 bbl. At the close of the year it was 49 bbl. The average daily pipe-line runs for domestic consumption were less than the state allowables recommended by the United States Bureau of Mines. There was a demand for Artesia crude for foreign export, which if included in the daily production for New Mexico would be slightly in excess of the daily production recommended for New Mexico by the Bureau of Mines. The daily average production for the year was 97,329 barrels. There were 622 completions in the state, of which 520 were oil wells; 16 hydrocarbon gas wells; 5 carbon dioxide gas wells, and 81 dry holes. Of the dry holes 38 were in or near-by proven fields and the remainder, 43, were wildcats. Five new fields were discovered in New Mexico during 1938, three in Lea County and two in Eddy County. Southeastern New Mexico Lea County.—The Monumcnt field was the largest producing field in Lea County, with 9,440,334 bbl., and was closely followed by the Eunice field with 8,872,335 bbl. The Hobbs field was third with 5,010,414 bbl. The greatest activity in Lea County was in the Vacuum pool, with 129 completions, of which 126 were oil wells and three were dry holes. The Texas Company completed its Corbin NO. 1 in the KW 1/4 SW1/4 sec. 10, T. 18 S., R. 33 E. in August. This well was drilled to a depth of 5118 ft. in a white sand, encountering salt water. It was plugged back to 4315 ft, and pumped 43 bbl. of 36" gravity oil in 12 hr. It was approximately 6 miles southwest of the closest production in the Vacuum

Jan 1, 1939

By Luis Elek

DEVELOPMENT of the cement industry in Mexico began some 40 years ago. It has gradually reached great importance in the economic life of the country and has contributed greatly to the technical and economical advances which have been so noteworthy, particularly during the last 15 years. From a modest start, the industry now comprises 18 cement-producing plants having a potential annual capacity of approximately 14 million bbl. About half the plants were built and equipped with secondhand machinery during the last world war when no new machinery could be procured. They will hardly attain full production before being modernized and reconditioned, a job now under way in several of the plants. At present, the yearly consumption is only about 8 to 9 million bbl but is steadily increasing. This is only a fraction of the cement consumed in the U.S.A., which is about 250 million bbl per year, although on the basis of consumption per capita per year, the figure is 1/3 bbl for Mexico and 1 2/3 bbl for the U.S.A. Cement consumption in Mexico is well above the average of all other Latin American countries, with the exception of the Argentine, and considering the potentialities and undeveloped riches of Mexico, the road construction and irrigation works, it is fair to assume that the Mexican cement industry will still prosper and expand in spite of temporary setbacks in the future caused by local events of economic or political nature. Portland cement is manufactured by burning a mixture of raw materials, one of which is mainly composed of calcium carbonates and the other of aluminum silicates. The most typical materials answering this description are limestone and clay, both of which occur in Mexico in many varieties. To be usable for cement manufacture limestone should contain at least 77 to 80 pct calcium carbonate. Lower grade limestone can be used for cement manufacture only if the lime content is increased by the beneficiation process, which has not yet been adopted by the Mexican cement industry. Most of the limestone used by Mexican cement plants has a calcium carbonate content of 90 to 95 pct and therefore requires addition of one or several correction materials. A typical composition of raw mix for cement manufacture is 85 pct limestone and 15 pct shale, clay or volcanic materials. Occasionally it is necessary to add a smaller amount of sand or other siliceous material to increase the silica ratio in the raw mix. Likewise, it is sometimes necessary to add 1 or 2 pct iron ore to facilitate fusion in the kiln and to obtain proper relation between alumina and iron oxide. After calcining and

Jan 1, 1953

By Bailey Willis

IN 1882, Peckham put forward a provisional hypothesis to account .or the distillation of petroleum.1 He did not formally state the hypothesis, but in a discussion of facts drawn from many fields he made it clear that he regarded petroleum, and especially the petroleum of the Pennsylvania fields, as a "fractional distillate produced under high pressure and consequently at a comparatively high temperature.?2 He quotes James Hall on the geology of the Appalachians and says:3 It is not necessary here to discuss the nature or origin of metamorphic action. It is sufficient for our purpose to know that from the upper Silurian to the close of the Carboniferous periods the currents of the primeval ocean were transporting sediments, sorting them into gravel, sand, and clay, forming gravel bars and great sand beds beneath the riffles and clay banks in still water, burying vast accumulations of sea weeds and sea animals far beneath the surface. The alteration, due to the combined action of heat, steam, and pressure, of the formations of the Appalachian system from Point Gaspe in Canada to Lookout mountain in Tennessee, involving the Carboniferous and earlier strata, distorting and folding them, and converting the coal into anthracite and the clays into schists along their eastern border, could not have ceased to act westward along an arbitrary line, but must have gradually died out farther and farther from the surface (source?). The great beds of shale and limestone containing fucoids, animal remains, and even indigenous petroleum must have been invaded by this heat action to a greater or less degree, and that "chronic evaporation" of Prof. Lesley must have been the inevitable consequence. From an investigation of the relations between coal and petroleum, White has" more recently concluded as follows: (1) Petroleum is a product generated in the course of the geodynamic alteration of deposits of organic debris of certain types buried in the sedimentary strata. (2) The quantity and characters of the oils generated are determined by: (a) the composition of the organic deposit at the beginning of its dynamo-chemical alteration; (b) by the stage in the progress of the dynamo-chemical alteration of the organic substances; (c) by the elimination, under certain conditions, of the heavier and more' viscous hydrocarbons through filtration incident to migration.

Jan 1, 1920

By H. J. Engell, W. Frank, A. Seeger

SWISHER and ~urkdogan' have determined the solubility of oxygen in a iron. They found it to lie between 7 and 10.5 at.-ppm at 881°C. Using earlier work on the permeability of oxygen in bcc iron,' they arrived at the following expression for the diffusion coefficient of oxygen in bcc iron (k = Boltzmann's constant, T = absolute temperature): where The present authors3 have estimated the activation energy QD for the diffusion of oxygen in bcc iron in two different ways from various experimental data.2'4"6 In the first method QD + QS (QS = heat of solution for oxygen in bcc iron in thermodynamic equilibrium with solid FeO) was determined either from data on the reduction of FeO with hydrogen4 or from measurements of the internal oxidation of silicon in a iron.5 Using an estimate of QS from investigations of the oxygen solubility in 6 iron2 (in thermodynamic equilibrium with molten FeO) Q = 0.97 ev or Q~ = 1.06 ev were obtained. From the magnitude of these values it was concluded that oxygen migrates interstitially in bcc iron and that consequently the activation energy QD for diffusion of oxygen has to be identified with the migration energy E~ of the oxygen atoms. Therefore, for a second estimate of QD from the diffusion coefficient of oxygen in 6 iron at 1450" ~,~ we used the theoretical expression:3 (a = length of elementary cube edge, m = mass of interstitially diffusing atom, sM = migration entropy), applicable to diffusion via the octahedral interstices in bcc lattices. Taking sM = 3.8 k (migration entropy of carbon in a iron), one gets Q = 0.90 ev. Hence, in Ref. 3 Q = (0.98 *0.1) ev was proposed as a plausible value for the diffusion energy of oxygen in bcc iron. sM + 9 (9 = solution entropy for oxygen in bcc iron) can be determined from permeability measurements.4 Using the above-mentioned estimate for QS , the following expression for the solubility c (atomic concentration) of oxygen (in thermodynamic equilibrium with solid FeO) in bcc iron was derived: From [4] the solubility of oxygen at 881°C in a iron is calculated to lie between 0.6 and 12 at.-ppm. We see that the solubility determined by Swisher and

Jan 1, 1969

By F. A. Orth

COAL-mine opera- tors face a difficul- ty in notifying men when there is no work. If the miners come to the shaft when there is no work, they must be paid, by agreement, two hours' wages. This involves a considerable loss since it is not uncommon to em- ploy two or three hun- dred men or more at a single shaft. Many mines have solved the problem by using an electric siren. This carries the "no work" message to all of the miners within a ra- dius of from one and one- half to two miles, so they do not trudge uselessly to work and the operator saves the two-hours wage payment. At the Valley Smokeless Coal Co., Johns- town, Pa., such a siren serves as a start and quit- work signal for three mines which previously re¬ quired three individual signal systems. Similar units are used by the Old Ben Coal Corp. mines, Dolly's Smokeless Coal Co., Rhonda Coal Co., Bird Coal Co., and hundreds of others. Many other applications of the electric siren have been found in mines. They are used on underground locomotives, to awaken miners in the morning, to tell them it is time to come to work, to sound the start and quit-work signal, and to warn of fire or accident. The sirens are most generally used to give a start and quit-work signal, fire, and general emergency alarms as well as no-work signals. They require 3 and 5 hp. to operate. The smaller unit has a sound radius of from three-quarters to one mile, while the larger siren can be heard over a distance of from one and one-half to two miles. The 5-hp. unit has been heard for as great a distance as 14 miles, and 10 miles is not at all uncommon. One of the outstanding features of the 3 and 5-hp. units, which is uncommon in the smaller sirens is that they may be adapted to sound code signals. When used to sound a fire or general emergency alarm the siren may tell at the same time where the fire or acci-dent is. When a remote control device is used with a siren it is possible to operate the siren from any number of distant points. Any number of "start" buttons may be placed at various places. By using one "start and stop" button where the remote control is mounted, and one or more "start" buttons at various places about the plant, it is necessary to run only two wires to the various "start" buttons. If "start" and "stop" buttons are used altogether, then three wires must be run.

Jan 11, 1927

SOME days ago a visiting member from Pittsburgh who is an ardent supporter of the Institute remarked: "There are a lot of men who would be members of the Institute if it weren't so expensive. It is not so much the $15 dues as the $20 initiation fee. This makes quite a hurdle, especially for the younger fellows." A little further conversation developed the fact that the member had never learned of the changes in the By-laws regarding initiation fees and dues made by unanimous vote of the Board of Directors last November. As a great many others doubtless are unaware of these changes, the substance of two of the amendments is here repeated. They provide: (1) That the initiation fee for Junior Members (heretofore ten dollars) he abolished. (2) That the age limit for entrance as a Junior Member be increased from 27 years to 33; provided further, that the period during which the dues of a Junior Member are ten dollars shall be a maximum of six years but in no event shall extend beyond his thirty-third birthday. The Junior Member gets the identical privileges enjoyed by his seniors and he likewise assumes the same obligations with the sole exception of the financial payments. This one exception is justified by the fact that the engineers of more mature years, who are established in the profession, - are able and willing to assume a slightly greater financial burden. In effect, it is a small subsidy for the younger men; but these in turn will later enter the group of those that give instead of receive assistance. The practical result is that an engineer under 27 can obtain every privilege and benefit of membership for six years on the payment of only $10 per year without any initiation fee. A man of thirty can do the same for a period of three years. Incidentally, a candidate applying for membership (either as senior or junior) in the next few months need pay dues for the second half of 1935 only. A Junior Member -can be enrolled with an immediate outlay of only $5. The Institute does not seek-members indiscriminately merely to swell the number. These facts are not presented as a "bargain" offer in any sense. The standards for admission are high and are watched zealously. But it frankly-wants to give qualified men who can benefit from membership every encouragement to apply. Naturally, the Institute does not want lack of accurate information regarding initiation fees and -dues to be a stumbling block to any that are eligible and desirous of enrolling. Members are urged to take it upon themselves to clear up misapprehensions on this point, particularly among younger engineers.-Editorial reprinted from MINING AND METALLURGY, May, 1935.

Jan 1, 1935

By F. B. Foley

With the possible exception of high-speed tool steel, the service demanded of rock-drill steel is probably more precarious than that of any other tool steel. Unaided by the helpful influence of alloys and dependent solely on the efficiency of the heat treatment applied for its ability to stand up under the abuse to which it is necessarily subjected, rock-drill steel is worthy of intensive study. For its heat treatment the smith has his fire, an oil fire perhaps, and a quenching bath; he judges the temperature by his eye. There are shops where excellent drills are produced by this method, but there are more where the product varies between very good and very bad. Pyrometers with specially designed equipment are used in but few cases. But the responsibility for rock-drill failures does not rest entirely on the smith. Little has been published concerning the efficiency of drill steel, though the Canadian Mining Journal1 published the breakage record of a large number of hollow drill steels. This record indicates that most of the breaks occur during the early life of the steel and that as a given batch of steel is used, its percentage of breakage decreases. This fact, the article points out, is at variance with the much-talked-of theory concerning failure from crystallization and fatigue. It seems to point to the fact that the greater part of drill-steel failure from breakage is traceable to faulty manufacture, resulting in defects in the bore of the hollow steel from inclusions of slag or oxides, etc. As this defective material meets with early failure, it is weeded out. In addition, some breakage may be caused by a lack of proper condition with respect to heat treatment of the steel as furnished by the manufacturer. In the article mentioned, the breakage of 1/14-in (3.17 cm.) hollow steel is given as 4.62 per cent. for the early period of use, with a decrease to 3.35 per cent. and 2.67 per cent. with time in use. For 1-in. (2.5 cm.) hexagonal hollow steel, the figures for breakage are 0.18 per cent. and 0.06 per cent.; attention is called to the great decrease in breakage by the use of smaller diameter drills. The figures are given as so many drills sharpened, but there is no way of determining the percentage of

Jan 1, 1922

By Richard A. Conkling

A shale layer, buried beneath two or three thousand feet of strata, in some instances, will upon folding become thicker in the synelines and thinner on top of the anticlines. This can be accounted for, in part, by the stretching on the crests of the fold and the compressing in the troughs; but this will by no means account for all of it, as is shown in the example herein set forth. It is my firm belief that the rest of the thickness is due to flow. What causes the movement, however, does not concern us here, SO long as there is movement, for this article purposes to show its effect upon the producing area of different sands. It is the author's hope, in this way, to drop a hint or two that may be valuable to the oil geologist, in making estimates of future productions and values of oil properties. An example will be given from property in the famous Gushing Pool in northeastern Oklahoma, where the author has had occasion to make a detailed study before recommending some property to his company, and has then been able to watch the results of this work. The author never mapped the surface structure in this pool, as this had been done by Frank Buttram when he was with the Oklahoma Geological Survey. We are using, therefore, a section of his map in this article for our surface contours. The main east dip comes farther east than this section shows. From the 10-ft. contours in Fig. 1, it will be seen that the surface folding is very slight, but in the contour map of the Bartlesville sand (Fig. 2), which was the greatest producing sand, we see much more complex folding. It seems that the folding becomes greater with the depth. Folding may have started in Middle Pennsylvanian times and continued through the Upper Pennsylvanian which is found at the surface. This may, or may not, have been the cause of the increase of folding with depth. However, the fact that mostly concerns us is the interval of shale between the Bartlesville sand and the Tucker sand. The Tucker is the next productive sand below the Bartlesville. Not enough wells have been drilled to the Tucker sand to make a contour map of it, but

Jan 1, 1917

By F. Julius Fohs

TAKING into consideration the present state of geologic knowledge and present economic status of the oil industry, we have attempted to outline the six principal districts in which oil occurs and new pools may be expected. The map, Fig. 1, also shows the location of the present productive pools-about 100 in number. The unshaded areas represent territory where drilling depths to known sands are prohibitive with present development and pumping methods, or such sands are absent or give promise of such small production that deep wildcat tests are unwarranted. They include, also, territory where the oil-source materials are absent or not of the right type; and where shales are insufficient in the stratigraphic section to prevent the escape of oil and gas. Some doubtful districts are also included, such as the Pecos Valley, where the percentage of rigid beds, sandstones and limestones may be too great; and the Nacogdoches oil field, where small shallow production is obtained but where deep or large production is unlikely. The map is not offered as final but in the hope that it may prevent the expenditure of large sums in attempted development of unlikely territory and as the warning that those who drill in the unshaded territory do so at great risk. Those who drill in such territory should have large sums available for pioneering and experimenting and only attempt it if they can well afford to lose the money expended. Search in the shaded or cross-hatched areas is hazardous enough and should only be undertaken after detailed geologic surveys. Out of a total area of 256,000 sq. mi., the oil and gas districts comprise about 80,000 sq. mi.; the territory embraced in these districts is shown in the shaded portions. This may ultimately be increased somewhat by the addition of some minor districts, but such additions will be offset by territory probably now included in the unshaded areas. The shaded areas probably contain 98 per cent. or more of the ultimate production of the state, despite the fact that they represent only 31 per cent. of the total area.

Jan 3, 1924