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By H. H. Campbell

The following paper deals almost exclusively with the results of practice at the works of the Pennsylvania Steel Company at Steelton, Pa. From the records of the furnaces at this plant, both acid and basic, large and small, are drawn the data for the various demon strations, and on a long and intimate experience with their opera tions are founded many theories and generalizations. It may seem that universal laws should not be built upon a basis so restricted ; but in reality the condition is the strongest guarantee of validity. Each table investigates some- certain variable, and by virtue of the common origin of the factors, we have good ground for assuming the corresponding agents to be equal. The examples may or may not be instances of good practice, and may be open to criticism if regarded solely as exponents of • metallurgical success. But it must be remembered that the lists are not made up of selected specimens, nor are they chosen to show su perior results; they are gathered to investigate, by strict scientific methods, the formula? of the operation. In such work no untoward results should be eliminated, save those which bear upon their face the stamp of experimental error. If the worst members be omitted, then the best must also be omitted. Only by using every available case can an honest attempt be made to deduce a true average. It is recog nized, however, that with the most careful selection it is difficult, if not impossible, to collect data representing universal conditions. In each table the records tell of a special practice, and all conclusions drawn from them are true only within the limits between which the equations have been integrated. Not assuming the prerogative of speaking for American melters in all the opinions herein expressed, nor acting as a camera in por traying an ephemeral state of national metallurgical development,

Jan 1, 1894

By Mark Sheppard

DURING the winter of 1937, the writer visited a West Virginia stone, quarry at which the overburden is stripped hydraulically. The quarry is in a bed of limestone, about 200 ft. thick, which outcrops on a hillside above a small river; the quarry face is 175 ft. high. The top of the stone is cut in all directions by erosion channels, which are filled with a tough, red clay. Some of the larger channels are 30 ft. deep and 8 ft. wide, The thickness of the clay overburden ranges from a few inches to 10 ft., the average being estimated as less than 3 feet. The topography of the district is rugged, and the hillside above the quarry face is not suited to the use of the usual mechanical methods of moving dirt. Until hydraulicking was started 10 years ago, the over-burden was dug by hand labor, dumped to the quarry floor and trans-ported to the dump in quarry cars, Cleaning deep channels was a slow and expensive process. When hydraulicking was started, the top of the quarry face was over 200 ft. above the level of the river. The pipe line was carried in a semi-circle around the top of the quarry about 200 ft. from the face and about 50 ft, above it. As there is no adequate supply of water above the quarry, the water must be pumped from the river: As quarrying pro-gressed the pipe line was moved until the discharge points are now over 300 ft. above the river. Water is pumped from the river by a four-stage centrifugal pump having a 5-in. intake and a 4-in. discharge. It is direct-connected to a 200-hp,, 2300-volt, 1760-r.p.m. induction motor. At 1760 r.p.m. the rated capacity of the pump is 750 gal. per minute under a head of 600 ft. The pump is installed in a house of frame construction on the river bank, about 10 ft, above normal water level, which also houses the pump for the mill-water supply. Above the pumps are hoisting hays into which the motors are raised whenever the river reaches flood stage.

Jan 1, 1938

By Samuel S. M. Chan

The magnetic susceptibilities of some ores and the major rock formations of the Precambrian Belt Supergroup in the Coeur d'Alene mining district were determined both in the laboratory by the use of the Gouy method and in the field with a Bison susceptibility unit. Trace element analysis of the same group of rock samples was also made using the atomic adsorption technique. Results of this preliminary study indicate that some correlation exists between the magnetic susceptibilities and the various rock formations. This may be useful for regional mapping and mineral exploration.

Jan 1, 1974

By Walter Harvey Weed

INTRODUCTION. IN a previous paper upon the enrichment of mineral veins by later metallic sulphides,† the writer has shown that certain masses of rich ores, such as are found in many mines, either near the water-line or as bonanzas in depth, are of secondary origin, and are due to a leaching of lean ore and the concentration of the material by reaction between the solution and the unaltered ore below. The geological and mineralogical evidence is believed to form an adequate basis for a chemical and physical explanation of the phenomenon. In the present paper the writer will give a brief synopsis of this theory, and will apply it more particularly to deposits of the precious metals, laying special emphasis upon the dependence of such enrichments upon the presence of iron sulphide (as pyrite, etc.) in the primary ore, and upon structural features which control the circulation of the enriching solutions below the water-level. It is believed that many, though not all, of the bonanzas and pay-shoots of rich sulphide ores, especially those carrying gold and silver, which are encountered in ore-deposits, are of such secondary origin. Apparently it is essential that the occurrence and structural relations of such ore-masses should be understood, as the success of the mine is often dependent upon the finding and extraction of these ores. A legitimate deduction, too, is that such ore-deposits decrease in value with depth. As my own studies have been mainly in Montana, my illustrations must be drawn from the ore-deposits of this and adjacent States, with such as I have noted in hurried visits elsewhere. The literature of ore-deposits doubtless affords also

Jan 1, 1902

By J. G. Baragwanath

CUBA'S lateritic iron ores, occurring on the northern coast of that island, though known to the Spaniards. did not receive any general attention until the close of the Spanish-American War. Preliminary studies of these deposits at that time indicated that the limonite contained small percentages of nickel and chrome, and it ryas subsequently discovered that although the average nickel content was only approximately 0.6 per certain limited areas of ore were suffiniently high in nickel to be considered commercial provided a suitable process fur its recovery could be developed. Early in 1937, Pardners Mines Corp. began a series of investigations which led to the development of such a process. Coincidentally, this company acquired option' on certain properties in the Levisa Bay and Moa Bay regions and conducted a systematic campaign of exploration by test pits and hand-auger holes in the course of which an aggregate of 90.000.000 tons of ore was developed in eight deposits.

Jan 1, 1945

By S. M. Marshall, A. C. Richardson, H. Y. Yancey

A year ago, Marshall and Bird presented a paper in which a new method of measuring the agglutinating power of coal was described.' The procedure used was to determine the strength of a button containing 10 parts sand and one part coal, formed by carbonizing the mixture in a crucible in an electric furnace. The result of the determination was reported as the total weight in grams required to bring about complete destruction of the button. Correlations were shown between the agglutinating value and some of the characteristics of the different coals that were investigated. This agglutinating test has been in use fairly continuously during the past five years for coals of widely differing coking qualities, and it has shown reasonably concordant results accurate enough for commercial use, although there are many features of the test which should have further scientific study. During the past year a study has been made of some coals of low coking strengths, and incidental to the main investigation some data which appear to be of interest and value were obtained on the loss in agglutinating power caused by exposure to the air. Three coals were investigated, all of which were of the Tertiary age; two were from one field in Asia, and one from a field in the United States. The three were similar, as shown by the proximate and ultimate analyses in Table 1 (moisture-free basis). Coals SA and RA generally contain about 5 per cent. moisture and coal P about 3.5 per cent. moisture on the as-received basis. The large difference in the ash contents of the coals, amounting to practically 10 per cent. between SA and RA, and P, makes difficult a direct comparison of their qualities. In the second section of Table 1 the figures have been put upon an ash-free basis., This table shows that these coals are closely alike. The ultimate analyses are almost identical except for the higher nitrogen content of

Jan 1, 1930

By Waldermar Lindgren

[The observations here presented were made during a short visit at Calico, in December, 1886. The accompanying map, which does not claim to be more than a careful sketch, is based on the position of a few mines obtained from Mr. F. Lewis, at Calico, and the plats in the Land Office with the patented claims. Only a few claims are shown by their boundary lines: as usual in mining districts, there is an enormous number of them, often conflicting or overlapping, the correct mapping of which would be useless for the present purpose. The rest of the topography and the drainage are mapped from sketches, aided by compass and aneroid. The elevations are taken from Daggett as base, the altitude of this station being determined by the railroad to be 2000 feet.] Until a few years ago the product of silver in California was of little importance, compared with that of gold, and often fell short of $1,000,000, the only noteworthy counties being Mono, Inyo and San Bernardino. About 1881, however, important discoveries were made in the deserts of San Bernardino, and the remarkable increase in the production may be seen from the following figures, taken from the Reports of the Director of the Mint: Silver Production of California. Of San Bernardino Co. 1883,. .. $1,460,000 $1,050,050 1884,. .. 3,000,000 2,550,000 1885,. .. 2,568,036 2,363,436 By far the largest portion of the product of San Bernardino is derived from the district surrounding Calico, although the success there has also given fresh stimulus to prospecting and mining in other parts of the county. San Bernardino borders towards the east on Nevada and Arizona, towards the south on San Diego County, California. Topographically, as well as geologically, the largest part of it belongs to the Great Basin. Broad shallow lake-beds or valleys with an elevation of 2000 to 3000 feet, are separated by low mountain chains and

Jan 1, 1887

Harry HaRkness Stoek, whose sudden death on March 1,1923, was a great shock to his friends in all park of the country, was a man of remarkable personal characteristics and mental ability. Through an acquaintance with him of nearly 35 years, during 12 yeam of which I was intimately associated with him both in business and socially, I learned to appreciate his many high qualities, his strict adherence to high professional and social ideals, and his lovable traits of character. In this appreciation I was joined by every one who was thrown in close personal contact with him. He was a conscientious student, not given to hasty judgments, but when he formed an opinion he was positive in upholding it. At the same time, he was most courteous and kindly in combatting that which he believed was erroneous. In fact, I never knew a person of his attainments more modest, forceful and kindly, or one who had a keener sense of clean humor. In his private life,he was a devoted husband and father, a consistent communicant and worker in the Episcopal Church, and was charitable in all things. In fact, his whole life was marked by helpfulness to others and a determined and successful effort to "make the world better by his having lived in it." Doctor Stoek was born in Washington, D. C., Jan. 16, 1866. His early education was obtained in the public schools of that city and he graduated from the Central High School in the first class to graduate from a high school in Washington. He entered Lehigh University in 1883, graduated in 1887 with the degree of Bachelor of Science, and after a year of post-graduate study in mining and metallurgy he received the degree of Engineer of Mines. During the summer vacation in 1885, he served as an assistant in the Department of Mineralogy in the National Museum at Washington, and during the summer of 1887 acted as U. S. Government inspector of dredging on the Tharnes River, Connecticut. From June, 1888, to January, 1900, he was assistant engineer for the Susquehanna Coal Co., at Wilkes-Barre, Pa. From January, 1890, to June, 1893, he was Instructor in Mining, Metallurgy and Geology at Lehigh University, and had charge of all courses in mining and metdlurgical design, and the visits of students to mines and metallurgical

Jan 1, 1923

Harry HaRkness Stoek, whose sudden death on March 1,1923, was a great shock to his friends in all park of the country, was a man of remarkable personal characteristics and mental ability. Through an acquaintance with him of nearly 35 years, during 12 yeam of which I was intimately associated with him both in business and socially, I learned to appreciate his many high qualities, his strict adherence to high professional and social ideals, and his lovable traits of character. In this appreciation I was joined by every one who was thrown in close personal contact with him. He was a conscientious student, not given to hasty judgments, but when he formed an opinion he was positive in upholding it. At the same time, he was most courteous and kindly in combatting that which he believed was erroneous. In fact, I never knew a person of his attainments more modest, forceful and kindly, or one who had a keener sense of clean humor. In his private life,he was a devoted husband and father, a consistent communicant and worker in the Episcopal Church, and was charitable in all things. In fact, his whole life was marked by helpfulness to others and a determined and successful effort to "make the world better by his having lived in it." Doctor Stoek was born in Washington, D. C., Jan. 16, 1866. His early education was obtained in the public schools of that city and he graduated from the Central High School in the first class to graduate from a high school in Washington. He entered Lehigh University in 1883, graduated in 1887 with the degree of Bachelor of Science, and after a year of post-graduate study in mining and metallurgy he received the degree of Engineer of Mines. During the summer vacation in 1885, he served as an assistant in the Department of Mineralogy in the National Museum at Washington, and during the summer of 1887 acted as U. S. Government inspector of dredging on the Tharnes River, Connecticut. From June, 1888, to January, 1900, he was assistant engineer for the Susquehanna Coal Co., at Wilkes-Barre, Pa. From January, 1890, to June, 1893, he was Instructor in Mining, Metallurgy and Geology at Lehigh University, and had charge of all courses in mining and metdlurgical design, and the visits of students to mines and metallurgical

Jan 1, 1923

By Lester Uren

Beginning with theoretical concepts of oil drainage, this paper demonstrates that the flow of petroleum into a well from a stratum of oil-saturated sand of uniform texture increases with the diameter of the well. This conclusion is supported by experimental evidence. It appears that if a well may be reamed to a diameter of 20 ft. within the oil sand, its production will be approximately doubled. A novel method is proposed for forming and supporting a cavity of such proportions within the oil-producing stratum. PETROLEUM occurs, in nature, as a fluid saturating the pore spaces between the grains of porous rocks or aggregations of rock particles such as sand, sandstone, conglomerate, shale, limestone, etc. The oil, under the influence of gas pressure, hydrostatic pressure, gravity, earth pressure, and, perhaps, other natural forces, is caused to flow through the porous "reservoir rock" into wells penetrating the stratum in which the oil occurs. The principal moving force is the pressure of dissolved or occluded natural gas within the oil, though this;, force is assisted by gravity and by the hydrostatic or buoyant pressure of ground water about the edges of the "pool." The wells, providing outlets to the surface, are centers of reduced pressure and the flow of rock fluids into a particular well is usually an expression of the difference in pressure existing between the space within the well and that of the stored oil .within the reservoir rock. The greater this differential pressure, the more rapidly will oil flow from the source rock into the well. Opposing movement of the oil from the reservoir rock into the well are certain natural forces related to the rock structure, such as pore friction and capillarity, and certain others related to the physical properties of the oil, such as viscosity and adhesion. The differential pressure between the well and the boundaries of the area drained by it must be sufficient to overcome the forces opposing flow if there is to be movement of oil into the well. If by any device the resistance to movement of the oil may be reduced, the oil will flow into the well at a more rapid rate and the effective area of drainage will be increased.

Jan 10, 1924

By John Gjers

Being on a visit to your great and prosperous country, and having been favored with an invitation to attend this meeting of your Institute, the author has been requested by your Secretary to give a short account of his invention of the " soaking-pit," which he has great pleasure in doing. The object of the soaking-pit is the rolling of steel ingots with their own initial heat, that is, to supply the missing link in that chain of metallurgical operations which Sir Henry Bessemer began in 1857, when he proved how it was possible to produce malleable iron or steel direct from the fluid cast-iron out of the blast-furnace, without any further direct use of fuel. The great Bessemer invention has revolutionized iron and steelmaking throughout the world; but it stopped short at producing the ingot, which, it was found, had afterwards to be heated in a furnace to enable it to be rolled or hammered; and it is only lately, twenty-five years after Mr. Bessemer's announcement, that the author of this paper has been able to show that furnacing can be dispensed with, and that it is practicable to roll a steel ingot into say a bloom, a rail, or a billet, with its own initial heat. It has no doubt suggested itself to many that there ought to be heat enough in the ingot just cast, for the purpose of rolling; and from time to time attempts have been made to utilize this heat; but such attempts always ending in failure, it became a settled opinion in the trade that it could not be done—an opinion which the author is aware that your late lamented countryman, Mr. Holley, than whom there was none more conversant with Bessemer steel-making, also entertained. But settled opinions sometimes prove to be great fallacies. As an instance, it is not many years since the opinion prevailed in the trade that steel ingots could not be rolled successfully, that is, so as to make good rails, unless they were first allowed to get quite cold, and afterwards heated. No greater boon was ever conferred on the

Jan 1, 1885

By W. B. Humes

The use of high vacuum on a large industrial scale in the ferrosilicon process for the production of magnesium marks the coming of age of an important new metallurgical technique. The economical production of reactive metals, such as magnesium, which combine with all the well-known furnace atmospheres, has until recently been successfully carried out only by electrolytic methods. It is now apparent that, through the use of high vacuum, the distillation or sublimation of many metals can be done industrially at much lower temperatures, and hence in much simpler equipment, than heretofore has been thought possible. At the beginning of the present emergency, when the ferrosilicon process of producing magnesium was brought to the fore, little was generally known about vacuum engineering, practices, and techniques. In a comparatively short time, the available equipment has been adapted, new equipment designed and built, and a fund of know-how evolved to make possible the production of thousands of pounds of magnesium per day at pressures less than 1/ r0,000 of an atmosphere. Pilot-plant operations have been consistently maintained at pressures even as low 2s one micron (0.001 mm.). These low pressures, which previously were regarded as prohibitively costly or impossible to attain, have been demonstrated as economically feasible on an industrial scale. Necessity for Vacuum The main function of vacuum in the ferrosilicon process, and hence in most vacuum smelting processes, is to lower the temperature at which the metal may be distilled or sublimed from the reduction mixture. A secondary function is to protect the distilled metal from attack by the furnace atmosphere and to permit the formation of a dense condensate. In the ferrosilicon process, magnesium is formed by the reaction between dolomite and ferrosilicon: 2(Mg0-Ca0) -\- HFeSU / t=> aMg + MFe + (CaO)2-SiO2 The metal is distilled from the pelleted charge at a free air pressure of about 0.100 mm. of mercury (100 microns). This low pressure is not needed for the reaction, but rather serves to protect the metal vapor from the oxygen or nitrogen of the atmosphere and permits the formation of a condensate free of pyrophoric material. The reaction proceeds at air pressures as high as several millimeters of mercury, and evidence has been offered to show that the actual equilibrium pressure of magnesium at operating temperatures of 2I50°F. is somewhat higher. Experimentation indicates that the yield begins to decrease at pressures above 500 microns. While no real operating data are yet available on the relationship between

Jan 1, 1944

TWENTY-FOUR of the 28 local sections and the two divisions of the Institute were represented at the meeting. Three sections failed to appoint delegates and two of those appointed failed to attend the delegates' meeting proper. Four sessions were held, two on Monday and two shorter adjourned ses-sions on Tuesday and Wednesday. Even at the end many things remained to be said and, in view of the amount of time the delegates lost from technical ses-sions the feeling was general that next year it would be advisable to hold their meeting the day before or day after the general meeting. Every part of the country was represented from Boston to Los Angeles and Seattle to Washington. All phases of Institute work and policy were taken up in the most informal way and the delegates will carry back to the sections, as they brought to headquarters, many ideas that will prove useful and stimulating. The time was divided between reports by the delegates on section activities and reports by officers of the In-stitute and of the various joint activities on the work at headquarters : A. D. Flinn told of the work of Engi-neering Foundation; W. V. Brown discussed the Em-ployment Service; J. A. Sohon explained what the Library is doing; T. T. Read told how the sections could help MINING AND METALLURGY ; H. Foster Bain discussed Institute affairs in general and asked and answered questions. An interesting new feature of the meeting was the appearance by request of Directors Turner and Smith of the U. S. Bureau of Mines and U. S. Geological Survey to answer inquiries as to the needs and work of their Bureaus. So much attention had been paid this year by the western sections to the diminished funds made available at Washington for research on mining problems that many questions came up. The accom-panying figures epitomize the answers.

Jan 3, 1928

By S. F. Emmons

There is, in the southern part of the State of Illinois, a series of deposits of fluorspar and galena in which the former mineral occurs on a scale of magnitude unequalled, so far as I know, in any other part of the world. In June, 1891, 1 had an opportunity of visiting the region of their principal development, near Rosiclare, Hardin county, Ill., and examined such of the mines in the vicinity as were accessible at that time. A very large proportion of the mining shafts that had been sunk in this region were unfortunately abandoned for the time being, and full of water. Moreover, detailed maps of the region are unattainable, no surveys having been made there, apparently, since the original land-surveys' of the early part of the century. In spite of these disadvantages I was enabled, in the few days at my disposal, to ascertain with sufficient accuracy certain facts not hitherto published with regard to these deposits, which seem worthy the attention of the members of the Institute. Before proceeding to a description of the deposits in question, I will give a brief abstract of the little historical and geological information hearing directly or indirectly upon them, which I have been able to find in existing publications. Historical. That the mineral was known to the Indians, is proved by the discovery, in some of the pre-historic mounds of the region,* of fluorspar, shaped into ornaments. The earliest scientific mention of its occurrence is found in the first volume of the American Journal of Science (1818+), which describes specimens obtained in the vicinity of Shawneetown by Mr. Joseph Baldwin. Similar notices appear in the same journal in 1820 and 1821, but without mention of the exact locality. They remark on the fetid odor which characterizes the mineral and its association with galena. Schoolcraft, as early as 1819, note: the occurrence of fluate of

Jan 1, 1893

By George Rice

TEN years ago, October, 1914, the author had the privilege of giving an-illustrated address on investigations of coal-dust explosions1 to this Institute at one session of its fall meeting in Pittsburgh, Pa. On the following day, the members had the opportunity of seeing a large-scale explosion test at the Experimental Mine near Bruceton, in which the explosion was made to follow a predetermined path by means of rock-dust barriers of various types, which had prevented the explosive waves from reaching the outlets of, the mine by the shortest paths.2 There was also shown a "home-made rock-dusting machine discharging the dust from a flexible nozzle, and a cement gun operated for the quick erection of a fire or ventilation stopping, such as might be put up after an explosion. Following that paper, there was presented a paper by J. Taffanel, Director of the Lievin testing station in the Pas de Calais, which reviewed the French coal-dust investigations.3 Another important paper was by Howard N. Eavenson, on Coal-mine Explosions Caused by Gas or Dust.4 This paper contains complete lists of explosions that occurred in North America and Great Britain, from early in the 19th century to 1912; in France to 1903, and in Belgium to 1909. No one can look over these lists without being struck by the great number of explosions and the, appalling aggregate of lives lost by them. Although they still happen, we-are hopeful that we have entered on a happier period of freedom from these dreaded visitations, as the result of great increase in knowledge; of the causes and means of prevention. Looking back over coal-dust investigations, there appear to have been periods of advance and of stagnation.

Jan 3, 1925

By Mark Sheppard

DuRing the winter of 1937, the writer visited a West Virginia stone quarry at which the overburden is stripped hydraulically. The quarry is in a bed of limestone, about 200 ft. thick, which outcrops on a hillside above a small river; the quarry face is 175 ft. high. The top of the stone is cut in all directions by erosion channels, which are filled with a tough, red clay. Some of the larger channels are 30 ft. deep and 8 ft. wide. The thickness of the clay overburden ranges from a few inches to 10 ft., the average being estimated as less than 3 feet. The topography of the district is rugged, and the hillside above the quarry face is not suited to the use of the usual mechanical methods of moving dirt. Until hydraulicking was started 10 years ago, the overburden was dug by hand labor, dumped to the quarry floor and transported to the dump in quarry cars. Cleaning deep channels was a slow and expensive process. When hydraulicking was started, the top of the quarry face was over 200 ft. above the level of the river. The pipe line was carried in a semicircle around the top of the quarry about 200 ft. from the face and about 50 ft. above it. As there is no adequate supply of water above the quarry, the water must be pumped from the river. As quarrying progressed the pipe line was moved until the discharge points are now over 300 ft. above the river. Water is pumped from the river by a four-stage centrifugal pump having a 5-in. intake and a 4-in. discharge. It is direct-connected to a 200-hp., 2300-volt, 1760-r.p.m. induction motor. At 1760 r.p.m. the rated capacity of the pump is 750 gal. per minute under a head of 600 ft. The pump is installed in a house of frame construction on the river bank, about 10 ft. above normal water level, which also houses the pump for the mill-water supply. Above the pumps are hoisting bays into which the motors are raised whenever the river reaches flood stage. An 8-in. suction line, equipped with a strainer and a foot valve, takes the water from a concrete sump at the edge of the river. The pipe line from the pump consists of 1750 ft. of 8-in. spiral steel flanged pipe and

Jan 1, 1938

By Mark Sheppard

DURING the winter of 1937, the writer visited a West Virginia stone quarry at which the overburden is stripped hydraulically. The quarry is in a bed of limestone, about 200 ft. thick, which outcrops on a hillside above a small river; the quarry face is 175 ft. high. The top of the stone is cut in all directions by erosion channels, which are filled with a tough, red clay. Some of the larger channels are 30 ft. deep and 8 ft. wide. The thickness of the clay overburden ranges from a few inches to 10 ft., the average being estimated as less than 3 feet. The topography of the district is rugged, and the hillside above the quarry face is not suited to the use of the usual mechanical methods of moving dirt. Until hydraulicking was started 10 years ago, the over- burden was dug by hand labor, dumped to the quarry floor and transported to the dump in quarry cars. Cleaning deep channels was a slow and expensive process. When hydraulicking was started, the top of the quarry face was over 200 ft. above the level of the river. The pipe line was carried in a semi- circle around the top of the quarry about 200 ft. from the face and about 50 ft. above it. As there is no adequate supply of water above the quarry, the water must be pumped from the river. As quarrying progressed the pipe line was moved until the discharge points are now over 300 ft. above the river. Water is pumped from the river by a four-stage centrifugal pump having a 5-in. intake and a 4-in. discharge. It is direct-connected to a 200-hp., 2300-volt, 1760-r.p.m. induction motor. At 1760 r.p.m. the rated capacity of the pump is 750 gal. per minute under a head of 600 ft. The pump is installed in a house of frame construction on the river bank, about 10 ft. above normal water level, which also houses the pump for the mill-water supply. Above the pumps are hoisting bays into which the motors are raised whenever the river reaches flood stage. An 8-in. suction line, equipped with a strainer and a foot valve, takes the water from a concrete sump at the edge of the river. The pipe line from the pump consists of 1750 ft. of 8-in. spiral steel flanged pipe and 800 ft. of 4-in. spiral steel flanged pipe. The connection from the pump

Jan 1, 1938

By Mark Sheppard

DuRing the winter of 1937, the writer visited a West Virginia stone quarry at which the overburden is stripped hydraulically. The quarry is in a bed of limestone, about 200 ft. thick, which outcrops on a hillside above a small river; the quarry face is 175 ft. high. The top of the stone is cut in all directions by erosion channels, which are filled with a tough, red clay. Some of the larger channels are 30 ft. deep and 8 ft. wide. The thickness of the clay overburden ranges from a few inches to 10 ft., the average being estimated as less than 3 feet. The topography of the district is rugged, and the hillside above the quarry face is not suited to the use of the usual mechanical methods of moving dirt. Until hydraulicking was started 10 years ago, the overburden was dug by hand labor, dumped to the quarry floor and transported to the dump in quarry cars. Cleaning deep channels was a slow and expensive process. When hydraulicking was started, the top of the quarry face was over 200 ft. above the level of the river. The pipe line was carried in a semicircle around the top of the quarry about 200 ft. from the face and about 50 ft. above it. As there is no adequate supply of water above the quarry, the water must be pumped from the river. As quarrying progressed the pipe line was moved until the discharge points are now over 300 ft. above the river. Water is pumped from the river by a four-stage centrifugal pump having a 5-in. intake and a 4-in. discharge. It is direct-connected to a 200-hp., 2300-volt, 1760-r.p.m. induction motor. At 1760 r.p.m. the rated capacity of the pump is 750 gal. per minute under a head of 600 ft. The pump is installed in a house of frame construction on the river bank, about 10 ft. above normal water level, which also houses the pump for the mill-water supply. Above the pumps are hoisting bays into which the motors are raised whenever the river reaches flood stage. An 8-in. suction line, equipped with a strainer and a foot valve, takes the water from a concrete sump at the edge of the river. The pipe line from the pump consists of 1750 ft. of 8-in. spiral steel flanged pipe and

Jan 1, 1938

By B. Foley

IN THE first report1 disks of steel of known composition and history were exposed, under carefully prescribed conditions, to impacts of explosion products resulting from the explosion of 50-gm. charges of explosives having well-determined rates of detonation, or to impacts of a weight of known mass, falling through measured distances. There were available at the Bureau of Mines Experiment Station five explosives, having rates of detonation of 5716, 4470, 3190, 2296, and 1523 meters per second. It being desired to continue this exposure downward, and no explosives with a lesser rate of detonation being at hand, resort was had to the impact of a falling weight, the differences in the velocity of impact being attained by varying the height from which the weight was allowed to fall. It was expected by this means to demonstrate experimentally that the development of Neumann bands was determined by the suddenness of the deformation of the metal in which they were produced. But while progressive deformations were obtained with the explosive arges, the falling-weight method failed because the tup was ogressively deformed, also the disks were so flattened as to be unfit for metallographic examination. A return, therefore, has been made to the use of explosives as the source of energy, an air-gap being interposed between the charge of explosive and the disk, as the effect diminishes as the function of the distance between the charge and the object on which the products of its explosion, or the shock wave from its detonation, impinge. The details of the arrangement of the tests by the air-gap method were the same as those described by Foley and Howell,2 except that after the system had been set up and the desired apparent specific gravity for the explosive

Jan 2, 1926

By BION J. ARNOLD

WE can, I think, rightfully claim, irrespective of our faults, that engineers must, in order to last as engineers, possess the qualifications of integrity, stead- fastness of purpose, ability to think straight, and to apply these qualities consistently and continually in their everyday work. All engineers know this, most of them conform, and in order to drive it home I might, if 'clothed with proper authority, preach to you at length, but I shall not take the chance. So I only want to make a suggestion or two to the young engineers. Have an ideal and work toward it. You will have your disappointments and your temptations but keep your record clean, and if anyone says you are foolish or ugly, or homely, or that you need a guardian, take the criticism with a smile, for he may be able to prove his contention; but if he attacks your integrity, strike at once and fight hard, for he has assailed not only your character but your principal asset as an engineer.

Jan 1, 1929