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By K. A. SPENCER

THE production of soft coal from strip mines in the United States has shown a remarkable growth in the last sixteen years, increasing from one and one-quarter million tons in 1914 to approximately twenty-two million tons in 1929. This is a growth of approximately 1660 p& cent, as compared with a growth of approximately 20 per cent in the underground mines for the same period. But even with this marked in- crease the total tonnage produced by open-face mining represents only 4 per cent of the nation's soft coal tonnage.

Jan 1, 1931

By W. A. Backofen, N. E. Paton

DEFORMATION twinning contributes to the plasticity of titanium and has been reported on {10i2}, {1121},{11221}, {1123}, and {1124} planes.' Twinning on {1011} has also been reported in commercially pure titanium as a result of quenching from 1000', but no reports of such twins occurring as a result of deformation alone are known to the authors. In this study single crystals grown from iodide titanium were compressed parallel to the c axis over the temperature range 25 to 800°C. From it has come evidence that (10il) deformation twins are the most common type between 400" and 800°C. Crystals about 6 mm high with a rectangular cross section measuring about 3 by 4 mm were used in the tests. Chemical analyses showed them to contain 220 to 250 ppm 0 arid 10 to 15 ppm N. The long axes of the crystals were made parallel to the c axis while the sides were parallel to (i100) and (1120), as shown in Fig. 1. The crystals were compressed between polished alumina platens with no lubrication, in a vacuum of 2 x lom5 torr. Between 25' and 300°C the predominant twinning mode was (11221, which is to be expected for this stress state. There was an abrupt change at 400°C, however, and from that temperature up to 800°C twinning took place almost entirely on (10i1 ). Twin planes were determined by the two-surface rnethd. Measurement of the crystal orientation within several (10i1) twins by means of polarized-light4 and transmission electron microscopy showed that the lattice reorientations were the same as those previously reported for the (10i l ) twinning in magnesium.' This reorientation is consistent with The calculated (10il ) twinning shear for titanium is 0.10, while that measured from surface offsets on a (1150) face, which is parallel to the shear direction, was about 0.15. Slip within the twins, or in the matrix adjacent to the twins, probably accounts for the larger measurement. Slip in both locations was judged to have occurred from observations on foils in the electron microscope.

Jan 1, 1970

By Albert J. McIntosh

In discussing the petroleum products situation the first thing that comes to mind is "what is happening to gasoline." Is the consumption increasing? How is the export market? What about imports? Are stocks on hand too high? Have we produced too much? This paper will attempt to answer these questions. Consumption of gasoline (motor fuel) in the United States in spite of the depression and the chaotic conditions of many industries has increased during 1931 about 2 per cent over 1930. This favorable factor was offset by a severe contraction in exports, which fell off about 30 per cent from 1930. This drop in exports was so large that very little more export business was done than in 1926 or 1927. Taking all demand combined, there was a decrease from the peak year of 1930 of nearly 11,000,000 bbl., amounting to slightly over 2 per cent. The units of the industry, though, should have expected some decrease and governed themselves accordingly. Let us see what they did. They reduced imports over 3,000,000 bbl., which helped. Production was cut 3,000,000 bbl., but this was not enough, so that stocks increased 1,800,000 bbl. whereas during the previous year stocks were reduced 2,500,000 bbl. It is apparent, therefore, that something was done to keep the industry in balance in regard to gasoline, but not enough. If the year had ended on Sept. 30, we could have said that production had been cut 19,000,000 bbl. and stocks had been reduced from the previous year, but the excessive production during the last three months of the year changed everything. It is a strange thing and worthy of note that the price of gasoline fell to its lowest levels when apparently the greatest improvement was being made, and that during the last quarter of the year prices started to improve, when, in spite of an improvement in total demand which approximated 1930, an excessive production caused an uneconomic condition to set in. Stocks on hand on Dec. 31 were unquestionably too high, possibly 10,000,000 bbl. more than was needed for a strong condition to obtain. It seems almost unbelievable that the industry would continue to produce

Jan 1, 1932

By J. E. Tobey

UNDER war conditions coal immediately assumes a position of highest importance for coal must carry the basic load for industry. The upward trend in production continued through 1941. Bituminous coal production alone about equaled the total output of bituminous and anthracite in 1940. The figures for 1941 approximated 500,000,000 tons for bituminous, and 54,000,000 tons for anthracite, and production of by-product and beehive coke exceeded that of the previous year. The coal industry, under the National Bituminous Coal Act, is going through a period of readjustment, and is beginning to stabilize itself under the statute. The Federal Mine Inspection Nill became law during the year.

Jan 1, 1942

By W. H. Smith

IN the course of an investigation on chromium containing minor amounts of alloying elements, the information herein has been obtained on the crys-tallographic orientations resulting from arc melting, rolling, and annealing. The chromium used in this investigation was electrolytic flake obtained from the Electro Metallurgical Co. This material was heated for 20 hr at 1600°C in hydrogen with a dew point of about — 100°C. The oxygen and nitrogen content of the chromium after this treatment was 0.0003 pct 0 and 0.005 pct N. Five pounds of this chromium were arc melted in a water-cooled copper crucible. After arc melting, the oxygen and nitrogen contents were 0.002 and 0.025 pet, respectively. A section of this ingot is shown in Fig. 1. By means of a back-reflection Laue technique, the crystal habit of the cast ingot was determined. As expected, it was found that the [loo] was approximately the axis of the columnar grains. In this respect, chromium behaves like other body-centered-cubic metals in that a cubic axis is normal to the cold surface of the mold. A slab cut from this ingot was rolled at 600°C as follows: four 30 pct reductions were made with intermediate anneals at 1200°C for 15 min. Rolling was done with the [loo] of the columnar grains in the rolling direction. Following the final anneal, an 80 pct reduction was taken at 600 °C. The final sheet thickness was ten mils. By polishing and etching, the thickness was reduced to four mils and the grain orientation determined by the transmission Laue method using molybdenum radiation with a zirconium filter. Fig. 2 is the (110) pole figure for this material with the ideal (100) [011] and (111) [112] orientations indicated. The orientation is typical of most cold rolled body-centered-cubic metals having the [llO] of the grains approximately in the rolling direction and the (100) planes approximately in the plane of the rolled sheet. There is also evidence of some 10) [1 orientation. The grain orientation of sheet rolled 40 and 80 pct in the same direction as before at 600°C followed by recrystallization at 12000 C for 15 min was determined by a back-reflection Laue technique. A random texture was found in both cases. This 1200°C 15 min anneal was found to give complete recrystallization and some grain growth.

Jan 1, 1956

By Stephen H. Stow

A relationship exists between the color and the chemical composition of the pebbles from the Bone Valley Phosphate Formation. Darker-colored pebbles are relatively high in iron oxide and relatively low in calcium phosphate when compared to lighter-colored samples; the brown color of the phosphate pebbles can be correlated with their iron content and the black and gray colors with their organic carbon content.1,3 It was anticipated that the darkness of a phosphate sample might be quantitatively measured by a simple reflectivity test and that the amount of reflected light could be correlated with the chemical composition of the rock, especially with the elements which cause the color and darkness of the Florida phosphates. Twenty-one samples of production grade phosphate rock from Hillsboro County, Fla., were studied. All samples were ground to -200 mesh for reflectivity tests and analyses. All analyses are accurate to well within ±2% of the reported value, except for aluminum and organic carbon, which are accurate to only ±15% of the reported amount. Reflectivity measurements were taken with a model 610 Photovoltmeter for tri-stimulus amber, blue and green, and white lights. Experimental procedures and data are available upon request. Results Table 1 contains linear correlation coefficients (LCC) for the element-reflectance relationships for the samples. The top portion of the table refers to the LCC between the percent of light reflected off the samples and the percent of a given element (or its oxide) as analyzed. In the lower portion of the table the LCC refers to the relationship between the same reflectance data and the chemical analyses which have been corrected on the basis of 0% acid insoluble material (chiefly quartz) in the phosphate rock. Each LCC presented in Table I is computed for the 14 coarser samples exclusive of the seven concentrates since the concentrate samples appear to have anomalous reflectivities upon comparison with the coarser grades. Only the most significant LCC for each element is presented in graphical form. Discussion of Data Iron: [Fig. 1] is a graph of the relationship between iron and reflectivity (LCC = - 0.98). A good correlation with Fe2O3, is expected due to the relationship between the tan (or brown) color and the abundance of iron oxide, the principal mode of occurrence of iron in Florida phosphates.8 Note the location of the seven triangles which repre-

Jan 1, 1972

By F. R. Pyne

The following notes are presented in an endeavor to point out the disadvantages attending the use of chrome brick in reverberatory furnaces in which are conducted the treatment of materials of such a nature that absorption by the brick is of too great value to be wasted, and these values must be recovered, if possible, in order to prevent metal losses that can not be tolerated. Several years ago one of the large Eastern copper refineries decided to utilize basic material in place of siliceous material in the walls of their reverberatory furnaces for the treatment of very foul blister copper, as the latter rapidly corroded the siliceous linings. It was also expected that there would be less slag formation, with a consequent decrease in the cost of treatment and a reduction in the metal losses. Magnesite brick were first used, but while the corrosive action of the foul material was greatly reduced, and the amount of slag formed was very much less, the magnesite proved to be unsatisfactory in certain parts of the furnace, because of its tendency to crack and spall badly when subjected to the alternate heating and cooling that takes place in a reverberatory refining furnace. This made many repairs necessary, and consequent frequent interruption in the operation of the furnace, which, together with the high price of the magnesite brick, ran up the cost of maintenance to an unreasonable amount. It was, therefore, decided to substitute chrome brick for magnesite brick in the parts of the furnace affected. The results, as far as the reverberatory furnace was concerned, were very satisfactory. The corrosion due to the action of the foul blister was small and the amount of slag formed was no greater than when using magnesite, and the tendency to crack and spall shown by the magnesite was eliminated. Gradually the use of chrome brick was extended to all furnaces, those treating blister copper as well as those melting cathodes, and the results were so satisfactory that the siliceous roofs were replaced by roofs of chrome brick except in certain places where experience showed a more satisfactory performance on the part of the silica brick. It was immediately recognized, for both the magnesite and the chrome brick, that the metal absorption was very heavy, but it was felt that the

Jan 1, 1918

By William Kent

ABOUT a year ago, the writer had occasion to assist Mr. John L. Gill, Jr., of the Pittsburgh. Car-wheel Works, in making a trial of his new testing machine. A piece of Bessemer steel, of about .34 carbon, was used as a test-piece, turned to a sectional area of one square inch for a length of five inches between shoulders, and pro¬vided with large round heads, which were fitted to what is called the " Wade grip." Measurements of elongation, accurate to , 1/10000 of an inch, were made by a special apparatus containing two micrometer screws, with electric contact attachment. The machine was operated by hand-power. Readings of elongation were taken at each increment of 2000 pounds stress per square inch, up to 44,000 pounds, the elongation corresponding to the latter figure being .0088 inch. The elongations up to this point remained almost exactly proportional to the stresses, the strain diagram, as shown on the Plate, from the origin to the point A, being a straight line (the deviation of no observation from the straight line being greater than .0002 inch). There being no indication of an approach to the elastic limit, the attendant at the hand-wheel and scale-beam was told to proceed as usual and move the poise forward 2000 pounds, or to 46,000, and turn the wheel until the beam was balanced. Noticing that the beam did not rise in the usual time, and that the elongation was increasing rapidly, the writer called to the attendant to stop turning the hand-wheel and to push the poise backwards until the scale-beam balanced. Instead of balancing at between 44,000 and 46,000 pounds, as was expected, it balanced at 40,000 pounds, and the elongation had increased to .0343 inch (or more than four times that recorded at 44,000 pounds), as plotted at the point B, the dotted line between A and B showing the supposed course of the strain diagram between these two points. Immediately upon recording the elongation the writer said to Mr. Gill, who was standing alongside: "This phenomena is without a parallel in my experience, and I know of but one way to account for it. The piece must actually be broken in its interior, through a flaw or weak portion of the metal. The test-piece is now equivalent to a tube, with

Jan 1, 1880

By W. O. Hotchkiss

AN ESSENTIAL mental equipment for planning exploration is the fullest possible. knowledge of the way in which the orebodies occur in the region to be explored, also the realization that in no mining district is this knowledge complete, and that new: facts of importance will he revealed to the explorer in every exploration if he is in the proper frame of mind to grasp them. The geology, of the ore deposits of the Gogebic Range for a long, time was thought to be relatively simple, but work in recent years, by several men, has proved that this is not the case. We now realize that we are far from knowing all the factors that have resulted in the localization of ore deposits. For example, we have long known that the intersections of the dikes and. the foot wall were favorable places to look for ore, but only within the last few years have we learned that there are several horizons' in the various members, well north of the foot wall, that are likely to carry ore. The influence of the numerous cross faults on orebodies is not known or appreciated beyond a general realization that they are important. Just how they may be favorable or unfavorable to the localization of ore is not known. Such elementary information as the positions of these faults is just beginning to appear on the mine maps. Such being the condition, one can hardly overestimate the importance to the various operators and fee owners of careful studies of conditions in their properties for the purpose of assuring themselves that they are not missing valuable ore-that they are doing all the exploration that their situation demands in order to secure maximum returns. Valuable ores have been missed in the past and will be missed in the future. Only with a complete knowledge of all the factors that have united to produce ore could anything else be expected. The purpose of this paper is to call attention to these facts briefly and to suggest a few of the principles that should guide effective exploration. The foremost principle is that the man who starts out with the idea that he knows all about the mine geology of the Gogebic Range is starting with a heavy handicap.

Jan 8, 1920

By Dubois Eastman

BEHIND the contrasting liquid-fuel technologies of Germany and the United States lie the basic differences of scarcity and abundance. The chemists and engineers of each nation have developed processes that accommodate available raw materials. In the United States, processing is based on an abundant supply of petroleum, which is refined into a variety of fuels and lubricants. Germany has little indigenous petroleum but has a readily available supply of coal that can be converted into liquid fuels and lubricants. As a result, in Germany several basic processes have been developed for the conversion of coal into synthesis gas (carbon monoxide and hydrogen). In turn, this gas is processed into products. As a normal function of its researches into petroleum processing, the petroleum industry in the United States has made careful studies of various conversion and synthesis techniques. A number of oil companies are carrying out independent development programs with the aim of synthesizing hydro- carbon products that can be marketed at a price that will compete with the price of refined petroleum products. American oil companies hope to perfect synthesis processes that will directly benefit the consumer. A good example of progress in these terms is the synthesis plant at Brownsville, Texas, which is based on the conversion of natural gas to synthetic fuels and other valuable products. When this plant is operated at near capacity, it is expected that the products will be able to compete favorably for the consumer dollar. The complete gasification of coal is a technique well rooted in history. As a controlled process on a small scale, it goes back centuries. As a practical technique on a commercial scale, it dates back to 1839, when "producer gas" appeared in Germany for limited industrial use. By 1873, "water gas," or "city gas" as it is sometimes called, was being manufactured commercially in the United States for use in heaters and stoves. The water-gas process was the cornerstone for modern synthesis. To older methods that were concerned only with carbon and oxygen reactions, it added hydrogen by means of steam. Thus far the goal of conversion was to produce gas for heating, lighting, industrial use, and cooking. The long step forward to synthesis was made in 1927, when Germany started to make gasoline from coal by means of the revolutionary Bergius hydrogenation process. A year earIier, Franz Fischer and Hans Tropsch had announced their process, which finally reached the

Jan 1, 1953

By W. M. Baldwin, C. R. Johns

Cobalt is reported1,2 to scale in accordance with the Pilling and Bed-worth3 parabolic law: where w = weight increase per unit surface area K = constant l = time The reported values of the parabolic oxidation constant, K, in the temperature range 600 to 1100°C follow an Arrhenius type of equation as inspection of Fig 1 shows. According to Valensi's theory5 on the scaling of metals where multiple-layered scales (for example, MeX, MeX2, and others) are possible, this fact could be construed as indicating that a single oxide only is formed on cobalt in this temperature range. Since the single straight line extends above 920°C where only CoO is stable in air (see Fig 2) it might be inferred that this is the only oxide formed on scaling. Arkharov and Voroshilova10 have studied the scales formed when cobalt is heated in air in the temperature range 385 to 800°C and report that CoO is indeed found in the scale but that CoO4 is also found as an overlay and in increasing amounts in the lower temperature ranges. No quantitative data regarding the relative proportions of the two oxides were reported. Again in the light of Valensi's theory this would indicate that the straight line in Fig 1 would be expected to undergo an inflection at some point in the temperature range 385 to 800°C. Chauvenet2 has studied the oxidation rates of CoO to Co3O4 and has found this reaction to proceed parabolically with time but reports parabolic scaling rates which are considerably (about ten times) larger than the scaling rates of cobalt metal itself. This is difficult to explain in terms of Valensi's theory although a full discussion of the possible discrepancy cannot be made in view of the lack of sufficient data. These points made an investigation of the scaling behavior of cobalt in air an attractive study. Discussion of Results Relatively large (approximately 95 sq cm of surface area) samples of 0.020 in. thick electrolytic cobalt strip,* sanded with 2/0 paper, were heated in air in a cyclone type furnace. The samples were weighed before and after the scaling treatment. The weight increases so observed obeyed the Pilling and Bedworth parabolic law at all temperatures studied. The parabolic scaling constants when plotted on a logarithmic scale as a function of absolute temperature are reproduced

Jan 1, 1950

By G. H. Cutter

SAFETY in mining depends on wire rope to as great, if not greater, extent than in any other industry. Sudden failure of a shaft-hoist rope might easily result in death or serious injury to the operators and workmen, extensive damage to expensive equipment, and a loss in production while repairs are being made. A wire rope is only as good as its component parts. It must be made from wire properly drawn and treated. It must be fabricated on machines large enough and capable of imparting the necessary qualities to meet the stringent service conditions. However, unless the fundamental requirement of good ropemaking is recognized, all other operations, no matter how carefully performed, will not impart reliability and quality to the product. This fundamental requirement is steel that is homogeneous, of high resistance to fatigue, and of a type suitable for rope wire. Most wire-rope manufacturers agree that rope wire should be made from acid-open-hearth steel. It is comparatively easy to meet the same physical properties with basic steel, but such properties are only part of the requirements for good wire. It is absolutely necessary, particularly for rope service such as mining, where reliability is essential, that the wire be uniform throughout its entire length. Most manufacturers feel that this highly important requirement is better met by acid-open-hearth steel.

Jan 1, 1936

By William Kent

About a year ago, the writer had occasion to assist Mr. John L. Gill, Jr., of the Pittsburgh Car-wheel Works, in malting a trial of his new testing machine. A piece of Bessemer steel, of about .34 carbon, was used as a test-piece, turned to a sectional area of one square inch for a length of five inches between shoulders, and provided with large round heads, which were fitted to what is called the " Wade grip." Measurements of elongation, accurate to 1/10000 of an inch, were made by a special apparatus containing two micrometer screws, with electric contact attachment. The machine was operated by hand-power. Readings of elongation were taken at each increment of 2000 pounds stress per square inch, up to 44,000 pounds, the elongation corresponding to the latter figure being .0085 inch. The elongations up to this point remained almost exactly proportional to the stresses, the strain diagram, as shown on the Plate, from the origin to the point A, being a straight line (the deviation of no observation from the straight line being greater than .0002 inch). There being no indication of an approach to the elastic limit, the attendant at the hand-wheel and scale-beam wits told to proceed as usual and move the poise forward 2000 pounds, or to 46,000, and turn the wheel until the beam was balanced. Noticing that the beam did not rise in the usual time, and that the elongation was increasing rapidly, the writer called to the attendant to stop turning the hantl-wheel and to push the poise backwards until the scale-beam balanced. Instead of balancing at between 44,000 and 46,000 pounds, as was expected, it balanced at 40,000 pounds, and the elongation had increased to .0343 inch (or more than four times that recorded at 34,000 pounds), as plotted at the point B, the dotted line between A and B showing the supposed course of' the strain diagram between these two points. Immediately upon recording the elongation the writer said to Mr. Gill, who was standing alongside: "This phenomena is without a parallel in my experience, and I know of but one way to account for it. The piece. must actually be broken in its interior, through a flaw or weak portion of the metal. The test-piece is now equivalent to a tube, with

Jan 1, 1880

By D. F. Haley

THE molybdenite deposits at Climax, Cool., have recently attracted considerable notice, because of their great size, as compared with other known deposits of the same mineral. Climax station, on the. Colorado Southern narrow-gage railway, was at one time the Fremont Pass station on the Denver & Rio Grande. It is 1412 miles northeast of Leadville, and exactly on the divide between the headwaters of the Arkansas and Blue Rivers. Climax station is 11,300 ft. (3444 m.) above sea level. The working tunnel of the molybdenum mine is about 1 mile from the railroad, and 900 ft. above it, at an elevation of 12,200 feet. The climatic conditions are severe, and snow can be expected during any month of the year. Winter sets in not later than Nov. 1, the snowfall is very heavy, and the ground remains covered with snow until June 1, and sometimes even later. From June 1 to Oct. 1, there is much rain and a little snow falls in the late afternoon nearly every day. In October, 1917, there was one of the biggest snowstorms and blizzards of the year. Being just on the divide, constant strong winds blow the fine, dry snow with such force that, during most of the winter, outside work of any kind -is accomplished under most trying conditions. Within a few miles of Climax, some of the richest gold placers of Colorado occur. One of them, McNulty Gulch, was just across on the northeastern flank of Bartlett mountain. This mountain, therefore; was well prospected, and the presence of a bluish mineral and a yellowish one resembling sulphur was known to the old prospectors. They thought for many years that the blue mineral was graphite, and it is difficult to say when it first became definitely known that it was molybdenite. Claims had been staked as .early as 1896, but it is evident that the prospectors at that time were looking for gold. In 1902; several claims were acquired by H. Leal, who drove a tunnel about 900 ft. (274 in.) long, probably to intersect a fault, which shows on the surface, and was thought to be a possible gold carrier. Gold was not found in paying quantities, but throughout its length the tunnel passed through a fractured silicified granite, showing a fairly uniform distribution of a fine-grained bluish mineral, which was finally determined as molybdenite. For several

Jan 8, 1918

By Arthur Knapp

The ordinary well log is subjected to a great deal of criticism, much of which is well founded. Sometimes, though, the difficulty in interpreting the log is due to the fact that the geologist or engineer using the logs does not know the limitations of the drilling method used. The rotary drill, especially, has inherent limitations that make it difficult to secure definite information at all times. The identification of well-defined key beds is about all that can be expected from the rotary log. The formation in a drilled hole, as reported by the driller, has a direct relation to the speed with which the drill makes the hole or to the reaction of the various strata on the bit, called the "feel of the bit." When this is not thoroughly understood by the geologist or engineer endeavoring to interpret the log, the result is an erroneous correlation with other wells or a discarding of the log as worthless. General Terms Hard and Soft.—Hard and soft are relative terms. In the case of well logs, they are very misleading as they are used in connection with both resistance to abrasion and resistance to percussion. In technical rock classification, hardness is relative resistance to abrasion. The term brittleness is used in connection with resistance to blows. These terms are misleading to the geologist or engineer who is not familiar with both the cable-tool, or standard tool, method of drilling and the rotary method. In the case of the standard tools, the driller's report of the hardness of the formation is in terms of its resistance to blows. For instance, a cable-tool driller might be able to make from 30 to 50 ft. a tour in a brittle limestone, which he would call soft and at the same time he might call a relatively soft (from a purely mineralogical standpoint) gypsum hard, because it is somewhat elastic and is not readily broken by blows. The rotary driller would reverse the terms. The limestone is hard in that it resists the abrasive action of the bit, while the gypsum might be soft in that it is readily cut by the rotary bit. It is rare that wells drilled by the standard tools are correlated with those drilled by the rotary, but the technologist who has worked with well logs from one system might be misled when working with the other.

Jan 1, 1921

I BELIEVE that my work would surely be host a seed without fit and that I would fail in that cause which disposed me to satisfy your request to write and form this work [75] if while laboring on it I did not tell you of the art of casting, since it is a necessary means to very many ends. I realize even more that I must tell as much as seems necessary since I have already demonstrated the methods of recognizing the natures and locations of the metals, of smelting and reducing them to their ultimate perfection, and finally have taught you to make their associations and alloys. It is especially necessary since this art and work is not well known, so that no one can practice it who is not, so to speak, born to it, or who does not have much talent and good judgment. For this reason and also because it is closely related to sculpture, whose arms are the support of its life, it is very highly esteemed. In order to describe the whole art in every part, I say that the greatest labors of both mind and body are required for its operations in the beginning, middle, and end. It is indeed true that these labors are endured with pleasure because they are associated with a certain expectation of novelty, produced by the greatness of art and awaited with desire, particularly since the artificer sees that it is an art pleasing and delightful even to ignorant men. As a result, as if ensnared, he is often unable to leave the place of work. To conclude: The outcome of this art is dependent upon and subject to many operations which, if they are not all carried out with great care and diligence and well observed throughout, convert the whole into nothing, and the result becomes like its name [cast away]. Therefore, having considered this work many times, with its extraordinary obstacles and the bodily labors heavy as a stevedore's, instead of exalting it with praise, I wish to say that it is such that a man of noble birth, even though he be gifted or be drawn to it by pleasure, should not practice it and could not unless he is accustomed to the sweat and many discomforts which it brings. He must suffer the great natural heats of summer as well as those excessive and continuous ones from the enormous

Jan 1, 1942

By Francis Donaldson

The direct injection of cement grout into water-bearing fissures as a means of checking or stopping the flow of water into shafts and tunnels has been experimented with for a decade or longer and seems to have been first attempted in Europe. The earliest application of which the writer has found a record was at a shaft sunk by the Mining Society of Lens; this is described by C. Dinoire in the Transactions of the Institution of Mining Engineers.1 It is only lately, however, that the process has been entirely successful. This success has been accomplished on the Catskill Aqueduct, now under construction by the city of New York. This aqueduct includes a number of deep pressure tunnels, reached by shafts for both waterway and construction purposes. In portions of these shafts and tunnels considerable underground water was met. The contract for the first of these deep pressure tunnels was let to the T. A. Gillespie Co.; this section is known as the Rondout Siphon. It leads under the Rondout valley at a depth of from 400 to 800 ft. and is about 5 miles long. The engineers expected that considerable water would be encountered, but fortunately this was not the case except at one shaft, known as No. 4, which penetrated the rock at a junction between limestone and conglomerate. Water-bearing fissures were encountered almost immediately. At a depth of about 200 ft. a flow of 1,500 gal. per minute was struck. The. shaft then contained as many pumps as could be used, and it seemed impossible to sink it further. After vain efforts had been made to proceed, John P. Hogan, a division engineer of the Board of Water Supply, suggested that cementation of the fissures be tried. The process was attempted for the first time in this country. Since the shaft was partly full of water it was necessary to drill grout holes with a diamond drill. Platforms were placed on the timbers at the water level, the diamond drill was installed and six 90-ft. holes were drilled in the bottom of the shaft. Several car loads of cement were pumped through these holes into the fissures, the drill casings being used for grout pipes. This largely cut off the flow of water from, the bottom and sinking could then

Jan 1, 1915

The officers and staff of the Petroleum Division are the servants of the members, and to the extent that the wishes of the members are made known and are practicable they will be carried out. The tentative plans outlined here are in general accord with previous custom, but modified by suggestions received recently from various members. The advice of all members is solicited, and it is hoped that the general expression on matters of policy can soon be facilitated by circulation of a questionnaire. Plans for two mid-year meetings of the Petroleum Division and for participation in the annual meeting at New York were inaugurated at the last annual meeting and are being carried forward as rapidly as possible in the belief that an early start will increase the possibility of finding the best available program material and permit the careful preparation, review, editing, and advance discussion of papers. While a number of papers have already been solicited, both members and nonmembers are hereby invited to submit additional papers, with the assurance that such papers will be given just as favorable consideration as the papers that have been requested. Mid-year meetings will be held at about the same time both in the Mid-Continent and California. The time will be selected if possible to coincide with the visits of President Lovejoy, who expects to be in California the last of September and in Texas early in October. Fort Worth, Dallas and Austin have been suggested for the Mid-Continent meeting. The Pacific Coast meeting will be held at Los Angeles. It is to be noted particularly that a Pacific Coast meeting was waived last year in favor of the annual meeting of the American Petroleum Institute, which was held at Los Angeles for the first time in nine years. It is hoped, and it was the understanding at the time among a number of individuals interested in both organizations, that in view of this action of the Petroleum Division the industry will give more than the usual support to the A.I.M.E. meeting this year. Ultimate Recovery is being considered as the keynote topic for the mid-year meetings. In view of trying financial conditions combined with an exceptionally high current potential rate of production, it is natural that the attention of the industry should be focused upon means of controlling production and reducing cost of operation. It seems that the Petroleum Division of the A.I.M.E., as a professional group, might

Jan 1, 1936

By R. S. Shoemaker, F. W. McQuiston

REFINERY SECURITY "Highgrading, " a polite word for stealing gold and silver, has been a way of life since the metals in native form have been mined or produced. Unfortunately, in the past, highgraders were not always severely prosecuted or even looked upon unfavorably in their communities. Recent high metal prices with attendent world wide publicity, however, has made highgrading or thievery again a serious problem in mines and plants. When a small button of gold the size of the end of ones little finger has a value equal to about one week's wages, the safe-guarding of gold production by enforcing tight security measures becomes a prime responsibility of management. The higher the gold price, coupled with unrestricted owner- ship, the greater the temptation to “get-your-cut”, and diligence by management must become an integral part of plant security. Primary security begins by knowing the expected gold production and the sampling of a gold ore mill feed for this determination has proved not reliable. However, solution flows can be accurately sampled and measured thereby closely predicting the gold recovered each day as precipitate. The progressive record of total ounces of gold contained in the precipitation press, referred to in cyanidation plants as I1solution calll1 predicts the accumulated production. The "callH is an important adjunct to security and extreme caution must be used so that the pregnant solution meter and sample are confined in a security area. It should be recognized that this key sample may be the target for Ifdoctoring" by trusted insiders (assay office employees) as a preliminary step for stealing precipitates and/or metal. Security measures similar to the following were adopted after one operation experienced a sizeable theft of gold precipitate and metal by trusted employees. The refinery area where precipitates are handled and melted to bullion and all other gold products are kept should be completely enclosed with a tight security fence preferably of solid construction. Access to this enclosure should be through one of two electrically controlled gates, one for personnel and another for occasional truck entrance. Admittance should be restricted to essential personnel who are required to sign a register in and out with the date and time. I£ there is a "back gate" to the restricted fenced area, it should remain locked except in an emergency and then opened only by a supervisor. Television monitoring cameras viewing the gate entrance and other sensitive areas connected to a viewing screen located in the general office afford visual observation at all times.

Jan 1, 1975

By R. P. Olsen, A. K. Schellinger

Molten silicate salts, the important industrial byproducts termed "slags," are known to be electrolytic conductors at furnace temperatures. This property is due to their partial dissociation into ions with the ion kind and size being closely related to the slag composition. Ionic conductance, in liquids, is a function of the viscosity, which in turn is a function of the temperature. It could be anticipated, therefore, that a semi-log plot of conductivity vs. reciprocal absolute temperature might yield a straight line, in the case of molten silicates and salts. As liquids, the viscosity of these slags should follow the Shepard1 relationship: log viscosity = A/T + B Then, if the resistance of the molten slag is directly proportional to the viscosity: log Rs = A/T + B Resistance measurements of molten halide salts,2 and silicate salts34 by various investigators have, indeed, shown this straight line relationship between resistance and temperature. A further relationship between the conductivity versus the degree of ioni-zation, the size of the ions, and the slag composition is, also, to be expected. Large ions, and fewer ions, would move more slowly in a potential field and could not carry as much current as smaller, more numerous, and mobile, ions. Conductivity, therefore, would be smaller in the presence of such large ions and higher slag viscosities. The conductivity-composition relationship is of considerable interest in the case of the industrial slags produced in iron blast furnaces, and non-ferrous smelting furnaces. These slags usually approximate three component systems with several minor components as impurities. At least one of the major components is commonly purchased for the sole purpose of rendering the slag less viscous at a reasonable furnace temperature. Should the conductivity be related rather directly to the concentration of such a purchased slag component (that is, CaO) instrumental measurement and control at the furnace might be possible. Modern tele-metric control methods in aqueous chemical process industries are often based on the property of conductivity of solutions, and its variation with composition. Investigators3 of the phenomenon of electrical conductivity in molten blast furnace slags have established that these systems show lines of equal conductivity on their ternary diagrams at one temperature level. These isocon-ductivity lines form closed contours on the diagrams, and at times, minimum areas occur at which these contours are essentially closed down to a point. The conductivity reading at such a point, at one temperature , would, of course, locate one on the diagram, and give the slag composition. Research in this field is understandably scanty. The reactive nature of

Jan 1, 1950