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By Chester Purington

PROBABLY no battleship of any great power save Japan could long remain in. the Pacific Ocean tinder present conditions, were it to depend for fuel supply on the hitherto developed coal or oil resources of any part of the adjoining lands in either hemisphere. This statement does not overlook the important but not inexhaustible oil fields of California, the bunker coals of British Columbia, nor the coals accessible and mined adjacent to Chinese water-ways. For both naval and merchant ships, however, modern practice seems to require high-grade Welsh or Pennsylvania bituminous even at great expense for transportation. Otherwise, we should not see British ships bunkering Welsh coal at Singapore nor the United States establishing a store of Pennsylvania coal at its naval base at Pearl Harbor, Hawaii. Compared with Atlantic coals, the best Miike and Nagasaki (Japanese) bunker coal, the Kailan coal of China, and the Welling-ton and Nanaimo coals of British Columbia, are dis-tinctly inferior, as one can soon learn from the chief engineers on Pacific liners. In addition to the coal used for steaming and bunker purposes, it is of increasing importance that an adequate supply of coking coal for metallurgical purposes should be made available at reasonable prices at industrial centers on the west coast of America, and at Japanese and Chinese coastal cities. The use of Chinese coking coals for smelting the iron of the lower Yang-Tse deposits is by no means so satisfactory as could be desired, while the poor quality. of Japanese coals for coking purposes is well known. If Russia, as seems not improbable, is to become a power on the Pacific in the course of the next few decades, she will doubtless develop an iron and steel industry in the Maritime Province, where an adequate and accessible supply of iron ore will necessitate a supply of coking coal.

Jan 9, 1923

By A. J. Opinsky, J. L. Orehotsky, L. L. Seigle

TUNGSTEN incandescent lamp filaments possess a typical structure of elongated crystals generated upon heating the silica-alumina doped wire rapidly to 2200°C or above.&apos; It is known that these very long grains exhibit a preferred orientation, but there is disagreement in the literature about the direction. Rosi,2 and later Rieck; reported that the <135> direction of the large grains in doped wire tends to be parallel to the wire axis, but other investigators have reported that <110> is the preferred direction. Some further investigation of the orientations of large grains in tungsten wire is reported in the following. In the first series of experiments, 6-in. lengths of wire were heated rapidly in a bell jar. Current was passed through the wires and within 15 sec the wires had reached the grain coarsening temperature. 2 min was the annealing time. Wires were heated in hydrogen, nitrogen, and vacuum. Later, wires were heated in an evacuated tube furnace in which the tube was brought from 1000°C to the operating temperature within 25 sec and held 5 min at temperature. Temperatures were measured with an optical pyrometer. After heating, the wires were electro polished and etched, and the orientations of the large grains determined by the Laue back-reflection technique. Most of the experiments were carried out on a single spool of 5-mil silica-alumina doped wire, but a few tests were made with 5-mil thoriated tungsten wire and 10-mil undoped wire. 5-mil silica-alumina doped wires were reduced to smaller diameters by electropolishing for one series of experiments. Orientations of the large grains in silica-alumina doped wire heated in various atmospheres are presented in Figs. 1 and 2 as plots of the direction of the wire axis relative to the cube axes of the crystals. For most of the conditions studied, the preferred orientation cannot be described as a single direction, but the points might be said to group themselves about the arc passing through <110> and <113>. This arc is the trace of the (211) planes and contains the <135> and <124 as well as <011> directions previously observed by other investigators. The preferred orientation of large crystals in silica-alumina doped tungsten wire might be most generally described, therefore, by stating that a (211 ) tends to be parallel to the wire axis. This is true also for wires reduced in diameter by etching and furnace heated, Fig. 2, i.e., the recrystallization texture is apparently unchanged upon removal of the outer layers and substantially independent of the temperature gradient within the wire.

Jan 1, 1962

By Oswald J. Heinrich

(Read at the Amenia Meeting, October, 1877.) THE deposit of rock salt along the shores of Lake Huron, in Canada, has been brought before the public during the last six months, in consequence of the developments made by the diamond drill at Goderich. It is likely to be of more than common interest in the future, since now actual operations have been commenced to exploit the deposit and work it by regular mining. The methods of mining rock salt being but little known in this country, it may be of interest to make a few general remarks in regard to them before entering, upon the description of this new mining enterprise. According to the conditions under which salt is found in nature, various methods have been resorted to, in course of time, to make it available for the human race. They consist in : A. Natural or solar evaporation. B. Artificial evaporation, either exclusively or in connection with the former. C. Mining the rock salt in its natural state, and converting it to a marketable product, if need be, by simply pulverizing it. Without going into the details of the various methods of making salt available in an economical point of view, dependent on its degree of purity, or on various local influences, we cannot refrain from. alluding to the general principles which influence the mining and manufacturing of salt in countries where they have been carried on for hundreds of years. ECONOMICAL CONDITIONS FOR SUCCESS. Salt being one of the articles of prime necessity, and one universally distributed throughout nature, it must always be sold at a comparatively low price. It would even be quoted in the market at prices far below those now ruling, if it were not for the high duties generally imposed upon it, for purposes of state revenues. But looking closer into the subject, it will be found that this duty is probably one of the least oppressive, although in some countries it exceeds sixfold the cost of profitable production. To produce the article at the lowest possible cost requires, therefore, a

Jan 1, 1878

By E. H. Rose

The present symposium on flotation machines provides a unique opportunity for group reappraisal of standard or habitual viewpoints. A symposium is by definition a trading post- for observations that might prove complementary when put together, thus leading to useful thoughts that might not have been evident from the original observations individually. The present paper, pertaining to power consumption in flotation, is deliberately an experiment of that kind. Data were solicited from the operating superintendents of several of the major flotation plants on this continent. The information received, covering a total of 14 separate operations in seven plants, has been collated in terms of power intensity; that is, the total power input per cubic foot of cell volume. This departs somewhat from the conventional expression of power per ton of ore treated, though the latter figure is also given for the plants concerned. Because of wartime restrictions, particularly in Canada, identifying names of plants and machines are withheld. Not as a firm conclusion, but as a tender for symposium discussion, the following points are made: 1. That flotation is a power operation in much the same sense as ball milling. 2. That contact time is the complement of power intensity and may be decreased as the latter is increased. 3. That a decrease in flotation power per ton of ore can result from an increase in power intensity. Analogy with Grinding In grinding, it has become axiomatic that the more the power put into a given operation, the greater the work performance. The analogous view is now proposed that the effectiveness of any flotation operation will be related to the mechanical energy usefully applied to that operation. Under this view, each increment of properly directed input energy should give either an increase in unit tonnage or an improvement in the metallurgical separation (concentrate grade or tailing grade), until either the theoretical limit imposed by mineral constitution or surface condition is reached, or until further increments of power become uneconomic under the law of diminishing returns. Thus, as in grinding, there are two forms of output that greater power input or improved utilization of power can produce. As for the law of diminishing returns, lower unit cost of power through improved generating efficiency in the past decade has pushed the limit back. Over and above this, however, there is strong indication in the operationg data herein presented that higher power intensity results in an actual economy of over-all power consumption. Like crushing and grinding, flotation accomplishes a rupture of the forces of molecular attraction, by taking particles from the common environment and placing them in the two separate environments of

Jan 1, 1947

By A. H. Grobe, F. N. Rhines

THE constitution of the indium-zinc alloy series has been investigated by Wilson and Peretti,1 who determined the liquidus and eutectic temperatures by the conventional method of cooling curves and the eutectic composition by analyzing eutectic exudations. Recent developments affecting the availability of indium and consequent increased interest in its applications make a more complete knowledge of the constitution of its alloys desirable. As a part of a program for the reexamination of the constitution of indium alloys by precision methods, the indium-zinc phase diagram [ ] (Figs. I and 2) has been redetermined in its entirety. The eutectic temperature (143.5°C.) reported by Wilson and Peretti has been confirmed exactly, but their value of the zinc concentration at the eutectic, 4 per cent, was found to be high; the new value is 2.8 per cent of zinc. There is also a rather large difference between the forms of the liquidus curves of Wilson and Peretti and those found in the present studies. The solidus curves herein have been located for the first time and the limits of solid solubility have been tenta-

Jan 1, 1944

Book Review MEXICO UNDER CARRANZA. By Thomas E. Gibbon, Los Angeles, California. Doubleday Page and Co., New York, 1919, 270 pp., 711/2 X 5 in. $1.50. A vivid, accurate, convincing summing up of the Mexican problem as it confronts us today, devoid of sensationalism or bigotry. A compelling narrative of the relations of the Carranza Government and our own from Oct. 15, 1915, when it was recognized as the de facto government of Mexico, to the present time. It shows the absolute lack of promises kept or lived up to either with its own people or the United States. This is not done by invective or the indiscriminate use of adjectives but by quoting from the instruments on record on both sides of the case. The driving of the Red Cross out of Mexico, which condemned many of the native peons to starvation, and the interference with the Pershing Punitive Expedition are merely mentioned, but the crying crime against the Mexican people, who have sunk to unbelievable depths of misery obscured, but not exceeded, by the sufferings in Europe, is held up in a clarified light. Two illuminating chapters are devoted to the character and treatment of foreign investments in Mexico, Which are a complete refutation of the common statement that Mexico has been exploited remorselessly by the foreign investor. The conces-sions given by Diaz in the days of his regime most condemned are nowise as large nor the land grants as extensive nor the title so absolute as those granted to the railroad builders of our own transcontinental systems and other of our nationally subsidized works. This is not left to further argument but is settled by quoting the various official instruments and not at all in a tedious way. The author&apos;s concluding chapter is a picture of the Mexican people from Aztec times, when they had reached a civilization which gave them a better calendar than the Roman Empire ever had until modern times, to their present unhappy and pitiful condition. He concludes, basing his findings on parallel historical downfalls of a once proud people, that present conditions are the natural result of the absolute domination of an alien minority. He grants, of course, that there are many estimable Latin-Mexicans of integrity, ability and charm, but maintains that the dominant minority has continually degraded in fulfillment of the sociological law that the sure revenge of the servile class is found in the corruption of the master class. The book is replete with historical and literary allusions which, added to the pleasing style of the accomplished author, make fascinating the account of one of the world&apos;s great tragedies. Mr. Gibbon is a lawyer who has spent much time in Mexico and shows an understanding of the native people not shared by all writers on the Mexican problem. A distinct addition to all literature on the subject. P. E. B.

Jan 8, 1919

By Robert E. Tally

Underground fires have been common in the mines of the United Verde Copper Co. for the past 22 years. The first fire started in the 300 Hampton stope in the fall of 1894, following a cave in that orebody. The soft and highly pyritic nature of the ores is responsible for most of these fires. Since ore characteristics, methods of mining and ventilation, have an important influence on mine fires, they will be described in this paper. Orebodies The ores are mostly chalcopyrite except on the upper levels where considerable chalcocite, black oxides and other secondary minerals occur. The orebodies are in the form of lenses and vary in size. Some are small, while others are several hundred feet in length by a hundred or more feet in width. These orebodies extend, in some cases, from the surface to the lowest levels of the mine and usually at a steep angle of inclination. There are three different classes of ores, classified in accordance with the gangue rock. The copper in all cases, except as above specified, is in the form of chalcopyrite. The largest and most important of these reserves are in a pyrite gangue. Next in order of importance are the schist ores and lastly the quartz porphyries. The pyrite, locally termed iron ores, average from 30 to 42 per cent. sulphur. The schist and quartz porphyries vary from 3 to 25 per cent. sulphur. Mining Methods All the orebodies were worked by the overhand square-set method of mining prior to 1908; since then the cut-and-fill, shrinkage and mill-hole systems have been largely employed. But 15 per cent. of the total tonnage now extracted is from timbered stopes. Most of this is from the upper levels where the ore is soft, heavy and more or less broken to the surface. Large reserves of these ores are being conserved for more efficient methods of mining.

Jan 1, 1917

By W. G. Matteson

THE origin of the salt domes of the Gulf coastal plain has been investigated by many of the most able geologists, but the problem cannot be said to have been satisfactorily solved. Since 1860, numerous theories have been presented, only to be discarded, at least in part, as more complete information revealed their fundamental weakness. Real progress toward solution dates from 1902, when Hill&apos; advanced the theory of secondary deposition of the domal materials from saturated solutions of hot saline waters ascending from great depths under hydrostatic head along structural lines of weakness. Shortly thereafter, Harris,2 using Hill&apos;s hypothesis as a basis, explained the doming and pronounced uplift associated with these salt cores as the result of forces exerted by growing salt crystals. This was a marked advance over the ideas of Coste3 and Hager,4 since no. evidence of igneous intrusives, as they assumed to explain the uplifts, had been found associated with the domes. Harris5 developed his theory until it offered such apparently plausible explanations of so many details of dome phenomena that his hypothesis and conclusions received widespread acceptance, despite some serious objections, and today his theory, somewhat modified, is considered by many able investigators to be the best explanation of, the origin of these domes. The immense production of oil per acre, the recognition of the high lubricating quality of the oil, the development and recognition of the efficiency and advantages of oil-burning vessels, with the, subsequent

Jan 2, 1921

By Samuel L. Hoyt

The present report represents that part of the work that has been done by the War Minerals Investigation, Manganese Section, of the Bureau of Mines, on the use of manganese alloys in open-hearth practice. The magnitude of the work and the number of people participating in one way or another make it difficult to acknowledge adequately the services of all who have contributed to the success of the work. It would be amiss, however, to pass to the body of the report without mentioning the hearty cooperation and willingness to assist of the various manufacturing interests. With such a sympathetic attitude toward this investigation, our work was assured of success. Inasmuch as the unhappy circumstances that rendered this investigation necessary have now passed, this report is made in the hope that the results may prove of some permanent value to the peace-time operation of our open-hearth industry. Broadly speaking, the purpose of the manganese investigation was to consider the most suitable means of utilizing our domestic supply of manganese and thus relieve, to the maximum extent possible, our shipping of the burden of importing manganese ores. It was not held that any decided shortage of manganese was imminent but rather that every legitimate means should be utilized for making our ship tonnage available to European service. While we have considerable metallic manganese in this country, it occurs largely as a low-grade mixture with iron or silica or with both. The open-hearth investigations, therefore, were carried on to determine the extent to which domestic or low-grade alloys could properly be substituted for high-grade alloys without materially impairing the steel production as to either quality or quantity. Also, it was held that such an investigation would yield valuable results to the steel industry as well as contribute, in no small way, toward directing future investigations in the same field. To the practical steel manufacturer, especially to him who felt no immediate concern about

Jan 1, 1920

By J. M. Callow

The selective action of oils for lustrous minerals was first disclosed by Haynes in 1860. In 1885, Miss Carrie Everson elaborated this idea and also disclosed the fact that acid increased the so-called selective action. Her patent called for oils, either animal, vegetal or mineral, also for an acid or salt. The process was tried out on a practical scale in Baker City and Leadville, in 1889, and failed: first, because, as has since been shown, of the unsuitability of the ore to flotation; and second, because the invention was too far in advance of the times. Then followed the Elmore brothers, first with their bulk oil processes and later with their vacuum method. The basic principles of oil flotation were undoubtedly covered by the above inventors, the work done since their time being merely a building up on ground work laid by them. Different kinds of oil, different quantities of oil, and all the varying degrees of agitation, were all exemplified and practiced by them in one phase or another, and the developments that have since been made are but elaborations of the fundamental principles laid down by Haynes, Everson, and the Elmore brothers. In 1902, the Potter-Delprat process was developed in Australia. In this process no oil was used, the mineral being raised by the generation of gas, brought about by the introduction of acid into the pulp. The mineral particles appeared on the surface of the separatory vessel, in the form of a scum or froth, buoyed up by minute gas bubbles attached to them. This no doubt first gave the suggestion of gaseous flotation. In 1902, also, Froment, an Italian, was granted a patent in which he combined violent agitation with oil and gaseous flotation, the gas being generated within the pulp, in much the same way as in the Potter-Delprat process. In the same year, Cattermole came out with a unique method. First, the pulp was emulsified with a small quantity of oil, by violent

Jan 1, 1916

By Bradley Stoughton

FRom 1886 to 1889, approximately, Henry M. Howe was engaged most actively in preparing his Afetallugy of Sieei, which became the foundation for his leadership in the science of physical metallurgy of steel. During the same period, Hadfield was developing the first of the industrially-important alloy steels, and Riley was initiating the commercialization of nickel steel. Both of these alloys are treated briefly in Howe&apos;s book; indeed, he missed practically nothing of interest in all the steel literature preceding 1889. There had been many good books on steel before his, but none of the same character. His genius, like that of Aristotle and Francis Bacon, manifested itself in the painstaking collection of data, followed by their coordination and interpretation. Not only manganese and nickel steels were discussed, but several which most of us, with our tendency to overlook the past, are wont to regard as exclusively recent developments, such as: silicon, chrome, copper, tungsten, vanadium, titanium, chrome-tungsten and many other steels. But Howe never devoted much special attention, in his writings, to alloy steels; the science of the relations of iron and carbon offered field enough even for his capacity for constructive thought. And, today we find the science of alloy steels in much the same condition as was the metallurgy of steel before Howe wrote his first great book. Many, many important facts have been presented to the world, especially by Sir Robert Hadfield, James Riley, Henri le Chatelier, Kotaro Honda and his associates, Maunsel White, Harry Brearley, and a host of others. Several books have been devoted wholly or chiefly to alloy steels, such as those by Hibbard, Mars, Heyn and Wetzell, Grube, Burnham, Gillett and Mack, Billón, Brearley, Monypenny, Becker, Savoia, Sauveur, Guillet, Tammann, Guertler, Goerens, Guia, Wuest, Ledebur, Schenck, Aitchison, Osann, Guettier, Buchetti, Escard. The vast number of data on the subject are indicated by a bibliography&apos; which was collected in preparing this address. It covers the years 1911 to

Jan 1, 1927

By J. O. Lewis, H. R. Pierce

Since the sudden revival of the air or gas-lift and its extensive use in the oil fields, many questions have arisen as to principles and as to their application under the conditions actually encountered in the field. Much has been written regarding both theory and practice, especially on the air-lift as applied to lifting water. Many statements have been made as to the use and benefits of the gas-lift, some of which are reasonable but many of which are unreasonable, many specialty makers claiming to have devices which operate in almost miraculous ways and even to generate energy nature never possessed. These claims are often based upon incomplete or inaccurate data. A review of the literature discloses many valuable articles, but it also discloses the need for setting out more clearly the different practical ends sought, and for working out specific engineering principles upon which to formulate the design and operation of gas-lifts to meet the desired ends within the limitations of field conditions. A check on some of the published information has revealed basic errors in the sources of data upon which conclusions have been predicated and has led the writers to doubt the value of a large part of the compiled data. The writers have concluded, therefore, that it will be opportune to direct discussion to the sources of error in the data now being collected, to recommend for consideration by the engineers some methods of collecting and correlating data, and to point out some of the factors relating to the application of the air-lift principle to oil production as dictated by the different economic ends sought, and the limitations of working conditions that may be met. Until these several considerations are clearly understood by the engineers, and the unreliable data have been sifted out and dependable data substituted, there seems little chance of evolving satisfactory engineering control for the air-lift. In the following pages no distinction will be made between gas-lift and air-lift, as they are generically the same.

Jan 1, 1928

By Dever C. Ashmead

FRom time to time metal-mine engineers have inquired why anthracitc mines and their preparators are rarely operated on the two or three-shift basis. The subject may be approached as affecting: labor, development, the underground workers, the preparator, the outside workers, capital, the supply account, power consumption, the storage of coal over various shifts, railroad car supply, and the market. Labor From the start, the adoption of a plan of three full-shift operations in a day would cause difficulty with the colliery employees, for they have never worked on that plan and would show their resentment by suspending work. Even if they could be induced to work according to this schedule they would not be as efficient, for they would be working more or less unwillingly at hours at which they are accustomed to rest. Operation on a three-shift basis would necessitate triple manning of each working place, and dissensions would arise between the men, for each shift would claim that the preceding shift had taken undue advantage and had not left as favorable conditions as it had found. To obviate these disputes it might be [necessary to let out the work to a contractor, who would hire his helpers to mine out the chamber, or breast. The state mining law requires that a miner be put in charge of each working place. To conform with this provision he would have to hire three helpers and two miners to mine the breast. The labor unions have been trying to abolish the subcontractor in mine work and any method of working that would cause his return, however innocent in purpose, would result in labor disturbances. It might be possible to form partnerships of three miners working a place together, but these men would be quite likely to have frequent dissensions as to the proportion of work performed by each shift. Only

Jan 1, 1923

By C. A. Wert, M. G. Coleman

The Zener relaxation in alloys in the a! solid-solution region of the Cu-Ni-Zn ternary system has bear investigated. Of the binary solid solutions that bound this region, Cu-Zn and Ni-Zn exhibit measurable Zener peaks whereas Cu-Ni does not. At constant atomic percent copper, the Peak height drops uni.forinly from the value in the Cu-ZTL binary to zero in CIA-Ali. The cariation of peak ternperatuve with composition is linear. At constant atomic percent zinc, the peak height in the ternary alloys goes through a large maximum as compared with the binary values. The temperature of these peaks varies smoothly with composition. The half-width of the peaks in the ter nary alloys, however, are much larger than those in the binaries. A large enhancement of the relaxation strength of the Zener relaxation in ternary Au-Ag-Zn alloys as compared to the relaxation strengths in Au-Zn and Ag-Zn binary alloys was observed by Firson and ert.&apos; Since this effect was unexpected, the present study was devised to investigate whether enhancement of the Zener relaxation in ternary alloys is a general feature or is particular to the Au-Ag-Zn system. We have chosen the Cu-Ni-Zn alloy system for this investigation. Measurable Zener relaxations are observed in both the Cu-Zn and the Ni-Zn binary systems, but not in the Cu-Ni binary system. A large solid-solution region extends to large concentrations of zinc, making it possible to vary composition of the alloys over a wide range without crossing phase boundaries. EXPERIMENTAL PROCEDURE Two series of alloys were prepared. the first at constant atomic percent copper, the second at constant atomic percent zinc. The compositions of these alloys are shown by the circles in Fig. 1. The alloys were prepared by melting the individual components, each of which had previously been vacuum-melted, in an evacuated quartz capsule in an induction furnace at 1500 C. The capsules containing the molten alloys were quenched in water to reduce coring. Any individual melt which exceeded 0.001 pct weight loss was discarded. The ingots were swaged to a 50 pct reduction of area and annealed for 1 week in an evacuated quartz capsule to aid homogenization. The alloys were then

Jan 1, 1967

By P. W. Bridgman

It is a commonplace that experimental physics in the last few decades has discovered manifold complexities in the atomic and subatomic levels, where it was thought for hundreds of years that no structure existed, as is witnessed by the derivation of the word "atom" itself. The field of exploration opened by the discovery of the electrical structure of the atom was so fundamental, rich and stimulating, that it has been almost exclusively cultivated by physicists since they obtained their first intimations as to the nature of the basic facts. Only within the last few years has it begun to dawn on us that we have overshot an enormous domain in which are situated many phenomena of fundamental importance for all the practical uses to which we put matter in our daily lives; the domain, that is, of most of the phenomena of interest to the biologist and the metallurgist. Furthermore, we are beginning to find that this intermediate domain is not entirely simple, but that it contains unsuspected complexities, some of them derived from the complexities of structure on the atomic and subatomic levels, and some of them emergent as matter collects itself into large aggregates, which often offer the key to the explanation of hitherto baffling large-scale properties of matter. Today I want to describe and consider some of these newly discovered complexities in the behavior of matter in bulk. The application to metallurgical problems is not always direct, but I hope to be able to suggest that such general notions as to structure as those here discussed must have important reactions on our attitude toward the problems of metallurgy. Three different sorts of phenomena of this kind to which I shall direct your attention are (1) the so-called structure sensitive phenomena, (2) complexities of such a nature that they are masked by the presence of extraordinarily small amounts of impurities, and (3) complexities depending on internal molecular rearrangements which can be understood only from the point of view of the quantum theory.

Jan 1, 1931

CHARGING of an open-hearth heat is begun as soon as possible after the previous heat has been tapped. Ordinarily, about 40 min. is required to drain and dress the furnace hearth, make up the tap hole, and perform routine repairs of the banks. Repairs to the upper back wall and to the front wall and jambs can ordinarily be done while the first scrap charge is being heated and are therefore allowed to wait in order to save furnace time. Any major repairs required on the hearth or other parts of the furnace necessitate longer delays, because such repairs must be made while the furnace is empty. Although charging practice varies considerably in detail with the type and proportions of scrap and iron used, many factors are common to all varieties of&apos; charge. Such general considerations are dealt with first. GENERAL CHARGING PRACTICE Charge materials are discussed in detail in Chapter IV; the present chapter is concerned with the charging, melting, and proportioning of the raw materials in the various types of furnace practice. Charging Equipment and Stock Handling. The physical equipment available for loading and weighing the stock, transporting it to the furnace, and charging it may have a major effect on charging practice. Limestone, scrap, and all other solid melting stock are charged mechanically by means of equipment described in Chapter I (see also Fig. 18, page 33). It is generally desirable to charge the scrap about as fast as the physical volume can be got into the furnace. A limiting factor may be the height to which the scrap may be piled in the furnace without deflecting the flame to such an extent that it will impinge on the roof or walls and thus damage the refractories, but light scrap may often be piled up near the roof since the flame usually "cuts it down" rapidly before impingement on any roof area can persist long enough to do appreciable harm. When the nature of the scrap and the handling facilities are adequate to meet the aim of rapid charging, little thought is given to this feature of operation. Unfortunately, at times

Jan 1, 1944

By Theron Wasson

The discovery of two new fields—the Reed City area of Osceola County and the Headquarters field, of Roscommon County —and the important development in Winterfield township, Clare County, again demonstrate the fact that it is the unknown and unexpected that enter very definitely into the oil-producing history of Michigan. This is particularly true in the area of thick glacial drift in the north central part of the state, where the new prolific fields have been discovered this year. This shifts the interest from the southwestern part of the lower peninsula, where a number of pools were rapidly developed during 1939 and 1940, back into the Central Basin area. As a result of strict proration in the new areas, the production for the state of Michigan for the year has not been as great as in 1940 or 1939. In 1941 the total production was 16,300,000 bbl., in 1940 it was 19,551,000 bbl., and in 1939, which was the peak year, it was 23,300,000 bbl. However, the discovery of the new fields this year nearly doubles the estimated reserves for Michigan reported at the end of 1940 In 1941 about 12,000,000 bbl. of oil was produced from the older fields, in which the individual well productions were so small that proration was not an important factor. The total production for the state from the discovery of oil in 1925 through 1941 now stands at 161,205,000 barrels. ActIVe Oil Fields Reed City Field.—In the Reed City field, Lincoln township, Osceola County, only small oil wells were completed during 1939 and 1940. The discovery of much larger production in wells drilled somewhat deeper, by The Pure Oil Co. and the Weber Oil Co., in the early part of 1941, led to the rapid development in this area. Some wells have had initial productions as high as 10,000 bbl. By the end of the year III producing wells were completed, with an average depth of 3600 ft., from the Detroit River formation of Devonian age. The entire development of the field to the end of 1941 was on 20-acre spacing. Headquarters Field.—The Headquarters field, which lies along the line between Clare and Roscommon Counties, was one of the most important discoveries of 1941 and will be the scene of vigorous development during 1942. Production so far has been from the Traverse lime at about 3400 it., and development has indicated that this is probably one of the most productive Traverse pools yet discovered. One well had been given a potential of 10,000 bbl. per day. Dry holes well located in relation to big producers indicate that it is a typical Traverse development. Winterfield Field.-This field, in Winter-field township, Clare County, was discovered late in 1940. By December 1941, 14 Dundee and 5 Traverse producers had been completed. The Dundee lime is found at a depth of 3750 it. and the Traverse lime at 3070 it. Producing conditions in the Dundee seem to be erratic because of varying porosity in the dolomit-ized limestone. Kawkawlin Field.—The Kawkawlin field, which was discovered by the Gulf Refining Co. in 1938, is in Monitor and Kawkawlin townships, Bay County. Small production

Jan 1, 1942

By Nicholas J. Grant, Klaus M. Zwilsky

EVER since the unusual high temperature creep resistance and structure stability of SAP (Sintered Aluminum Powder) and similar aluminum-alumina alloys were reported,&apos;," there has been a need to determine whether other metal-metal oxide (or other hard stable particle) alloys, not so ideal as the Al-Al 2 O 3 system, would show similar high temperature strength and stability. Of the many possible methods of obtaining a metal-metal oxide alloy,a one that offers many practical and theoretical advantages is the simple mechanical blending of metal powders with hard stable particles, followed by pressing, sintering, and hot extruding. With this purpose in mind copper powder and silica and alumina were selected for experimentation because these materials are readily available, cheap, reliable, and lend themseives te the simplest processing and testing. Starting Materials—Two sizes of electrolytically deposited copper powders were used, a —200 mesh powder referred to as A powder in this investigation and a —325 mesh powder referred to as C powder. Silica was added in the form of pure Potter&apos;s flint from which a —10µ fraction had been separated. Alumina of the a variety was used in two size ranges. The first was a —10µ fraction separated from a coarser aggregate, the second a commercial product of 0.3µ average diam manufactured by Linde Air Products. Preparation of Powders—Five-hundred gram batches of A copper with 1, 3, and 10 volume pct of each of the three oxides mentioned above were prepared, as well as C copper containing 1, 3, and 10 volume pct of —lop silica. Powders were weighed out carefully and blended by ball milling in air for 24 hr. Since this treatment resulted in surface oxidation of the copper, the charge was hydrogen reduced at 260°C for 5 hr. The next step consisted of hydrostatically compacting the powder into a shape suitable for the required hot working. For this purpose a slug about 11/2 in. in diam and 31/2 in. in length was produced by placing the mixed powders into a rubber sleeve, holding in a perforated steel canister, and rubber stoppering at the ends; the assembly was then subjected to a hydrostatic pressure of 50,000 psi. The air was evacuated from the assembly prior to pressing in order to prevent

Jan 1, 1958

By C. A. O’Connell

Surface exploration drilling at Mufulira started in 1928, with drillhole No. 1 intersecting ore near the eastern fringe of the deposit. Subsequent drilling along strike intersected ore until the western fringe was fixed some 7500 ft west of drillhole No. 1. Further intensive drilling down dip disclosed a large triangle of ore with its apex 3350 ft deep. It contained approximately 11 6 million tons of ore at 4.41% total copper in three superimposed orebodies. The east and west limits of the orebodies were presumed to have a pronounced rake to the north with a strike length of 8000 ft. Subsequent exploration underground seemed to bear out this presumption to the 1150 ft level. In 1947, attention was directed to the area west of the known orebodies in conjunction with plans for increased production and increased depth of the mine workings.

Jan 12, 1962

By G. Willard Quick

TENSILE tests of rail steels at elevated temperatures&apos;&apos; have shown that certain rails, in addition to having low ductility in the well-known bluebrittle range in the neighborhood of 200° C., have marked reduction in elongation and reduction of area in the temperature range from 400° to 700° C. This range of low ductility was called "the secondary brittle range" and the phenomenon, "secondary brittleness." The question naturally arises as to whether this property of the steels would be shown by impact tests performed in the same range of temperature. If so, the impact test, as suggested by Gillett3 would be a simpler and quicker method for the routine examination of steels at elevated temperature than the tensile test. A number of investigators have reported results of impact tests on steels at elevated temperatures, in which the energy absorbed decreased with increase of temperature above 200° or 300° C. Langenberg4 performed Charpy impact tests on several steels at temperatures ranging from room temperature up to 1000° F. (538° C). His results showed an increase in the energy absorbed in specimens tested in the range from room temperature to 200° or 300° C. and then a gradual decrease in the range, 300° to 538° C., the maximum temperature used. Greaves and Jones5

Jan 1, 1932