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Jan 1, 1944

Jan 1, 1937

Jan 1, 1944

By J. L. Carne

Careful sampling is necessary to maintain sulphide-oxide ratio of open-pit and underground ores.

Jan 6, 1951

Jan 1, 1941

By F. W. Gordon

Since the waste gases of the blast-furnace came to be generally utilized in heating the blast and raising steam, the gradual improvement in the economy of fuel, mainly through the nse of higher temperature in the blast, has impoverished the gases. The increased output per unit of measurement of the furnace, and the increased height of the furnace, have markedly increased the resistance to the blast, thus enormously increasing the duty required from the gases. In other words, a gas reduced in heating power by a further dilution of CO, is required to raise the temperature of the blast to 1800' Fahr., where formerly 600' was a good temperature, and at the same time to raise steam enough to drive the air into the furnace at a pressure of from four to eight pounds in coke practice, and from eight to twelve pounds in anthracite practice, and also pump at least double the water formerly used at furnaces. Hence the necessity for the employment of the best scheme for thoroughly consuming these gases with the least dilution of air, and the use of the best device for absorbing the heat prodnced for the purposes above mentioned. In a former paper before this Society the writer called attention to such improvements as had been made by his firm, by which it was claimed 1400' Fahr. could be maintained in the blast by a less consumption of gas than was required to maintain 900' when using pipe-ovens; and it would not be too much to say that 1600' Fahr. might now be written in place of the 1-400. The object of this paper is to give the practice of our firm in the

Jan 1, 1884

This study of engineering education arose out of the action of a joint committee on engineering education, representing the principal engineering societies. The committee had gathered so much material that it decided the work could best be carried out by some one trained in applied' science, who would devote his entire attention to the study.. The Carnegie Foundation therefore asked Prof. Charles R. Mann, of the University of Chicago, to undertake the work. After making a thorough study Prof. Mann has made a most comprehensive report. In it he says: The engineering schools of the United States began their work upon a definite teaching plan and one that had at least pedagogic consistency. But during the past half century the course of study has been overlaid with many special studies intended to enable the student to deal with the constantly growing applications of science to the industries. As a result, the load upon the student has become so heavy that there is a feeling that the students fail to gain a satisfactory grounding in the fundamental sciences and do not fulfil the expectations of engineers in d manufacturers in dealing with the practical problems with which they are confronted on leaving school. At present 60 per cent. of those who enter the schools fail to graduate, still many of them persist in engineering and make a success of it. It is evident, therefore, that the present systems of admission are not satisfactory. If a group of schools will take up the careful study of their entrance systems and experiment with objective tests and records of the students' youthful interests and achievements, the percentage of elimination can be reduced to at least a fourth of its present size, with an enormous saving of time, energy, and money for both student and school. The number of required credit hours per week should be less than eighteen, preferably sixteen. The few experiments that have been made indicate that college students do their best work when not more than five subjects are studied at a given time.

Jan 1, 1919

By I. Cadoff, J. P. Nielsen

The Ti-C phase diagram exhibits a peritectic point at 1750°C and 0.8 pct C, and a peritectoid point at 920°C and 0.48 pct C. The maximum solubility of carbon in a titanium is 0.48 pct. The 6 region containing the Tic compound (20 pct C) extends to 11 pct C at the peritectic temperature. THE interest in the Ti-C alloy system stems from the fact that carbon occurs as an impurity in titanium alloys when graphite electrodes or graphite crucibles are used in their melting. Since titanium-base alloys are still in the development stage, some virtue may be found in carbon addition to titanium. The Tic compound is currently emerging as an important powder metallurgy base constituent similar to the WC compound. Ehrlich' identified the phases and structures present in the Ti-C system. The peritectoid region of the phase diagram was investigated by Jaffee et al." A preliminary diagram based on theoretical considerations was proposed at the outset of this research." The Tic compound has been investigated extensively and has been reported on in a large number of papers. Experimental Procedure Arc-melted alloys of 24 compositions in the range 0 to 20 wt pct C were investigated using metallography, X-ray diffraction, and, for the liquidus and solidus regions, incipient and complete melting. All alloys were prepared from iodide titanium (New Jersey Zinc Co., 99.95 pct Ti minimum) and spectroscopic grade carbon (National Carbon Co.). To prevent carbon spattering during arc melting the carbon was encapsulated in titanium. For alloys containing less than 1 pct C the powder was inserted into a capsule formed by drilling a hole in the as-received rod. For higher compositions, capsules were formed from titanium sheet. Arc Melting: The charges were melted in the copper-hearth cold electrode furnace shown in Fig. 1. This furnace is similar in principle to the all-metal unit adapted for titanium melting at Battelle Memorial Institute.' The transparent pyrex walls giving unlimited visibility during operation and the multiple-

Jan 1, 1954

Jan 1, 1944

By John R. Burger

Industrial mineral mines that have recently been opened, or soon will be opened in the northern circumpacific will produce potash in Canada, Mexico, and Thailand; phosphate in the US, Mexico, and Colombia; soda ash in the US; and chromite in the US and the Philippines.

Jan 1, 1982

Jan 1, 1896

By L. W. Jones, B. H. Bennetts

The removal and disposition of large quantities of slag from blast-furnaces is a question of great importance in the design of works, and various methods have been devised, from time to time, in order to take the best advantage of local conditions. With blast-furnaces treating copper-ores or lead-ores, it is necessary to use a fore-hearth, or matte-settler, in order to collect, if possible, every particle of valuable matte which, otherwise, would be carried away with the out-flowing slag. In all of these cases, the slag overflowing from the fore-hearth is caught in pots and then conveyed to the dump. If the slag is of no value and the necessary water-supply, grade and dumping-space be available, the disposal of the slag by granulation is by far the cheapest and best method. It involves a minimum of labor, both at the furnace and at the dump; and it permits a continuous outflow of slag from the furnace or settling-pot, thereby avoiding frequent tapping and plugging. When the conditions of water-supply, grade and dump-area will not permit slag-granulation, there are three other methods in common use. Large steel or cast-iron pots, or ladles, supported by trunnions on heavy cars which are moved by steam-, air-, or electric locomotives; some type of mechanical conveyor; and small pots or buggies moved by hand. The pots on the slag-cars are generally circular or oval in shape, and each one contains from 15 to 40 or more cu. ft. of molten material. The mechanism for tipping them is more or less elaborate; and, as a general rule, the slag is dumped alongside, and quite close to, the track. They are more or less costly to construct and to keep in repair, and, in order to use them to best advantage, it is necessary to have a good elevation of track above the dumping-ground ; furthermore, the rails must be of heavy weight, and well-supported on heavy ties. Other disadvantages of the slag-pots are—1, that the slag cannot be removed continuously

Jan 1, 1906

By P. Dosmond

In ore mining technology, the loading and hauling operations are undoubtedly the area where the most spectacular progress has been made during the last twenty years. In the iron ore mines of Eastern France production of 62 million tons for 1962 and 19863 constitute a worthwhile experience worldwide. These deposits which are located in Lorraine are of sedimentary origin and they contain many mineralized horizons with workable seams varying in depth from 330 to 830 ft.

Jan 1, 1970

Joseph W. Richards was elected Vice-president and Director to fill the vacancy caused by the election of Philip N. Moore to the presidency. Benjamin B. Thayer was elected Director to fill the, vacancy caused by the election of Charles W. Goodale as Vice-President and Director. Sidney J. Jennings was elected First Vice-President of the Institute. George C. Stone was elected Treasurer of the Institute. Rossiter W. Raymond was appointed Secretary Emeritus of the Institute. Bradley Stoughton was elected Secretary of the Institute. Burr A. Robinson was appointed Assistant Secretary of the Institute.

Jan 4, 1917

By William Kelly

An exploring-drift, on the bottom level of the Curry mine, at Norway, Mich., on the Menominee range, cut a stream of water, which increased considerably the expense of pumping. The hope that the supply would drain off was not realized. It was decided to build a dam in the exploring-drift, as it was estimated that the cost would be recovered by the saving in fuel in less than two months.

Jan 1, 1898

By H. T. McAdams

Current theories of fracture maintain that brittle materials contain flaws or regions of weakness at which fracture originates. Whether a particular flaw grows depends upon the stress distribution in its vicinity and upon the presence of other stress relieving mechanisms capable of absorbing the applied energy. Under load, therefore, certain of these flaws will be activated, and the resulting fragments will have a size distribution determined by the spatial distribution of active flaws. Gaudin and Meloy,1 assuming a random occurrence of flaws, have derived the size distribution of fragments as

Jan 1, 1965

By Allan J. Clark

In his paper on "The Accumulation of Amalgam on Copper Plates,"f Mr. R. T. Baylies records the fact that at the Drumlummon mill, at Marysville, Montana, a series of tests proved that silver, instead of showing a strong affinity with the amalgamated surface of the copper plates, gave evidence of a persistent tendency to escape amalgamation; the fineness of the amalgam, as measured in gold, being highest nearest to the battery, and giving place to a constantly-increasing proportion

Jan 1, 1900

By Junnosuke Yamamoto

Substituting sodium hydroxide for sodium carbonate as a binder in a glass batch yields harder pellets with a lower melting point. This paper explores the degree of NaOH substitution that is feasible, and compares pellet hardness, and amount of dusting with the degree of NaOH substitution. The effects of the the amount of soluble silicate in the pellet and residual hydroxide concentration in the pellet on pellet hardness are also studied.

Jan 1, 1977

ZAY JEFFRIES, ? Cleveland, Ohio (written discussion?).-Mr. Miller's work on the path f rupture in fusion welds is fundamental. He is to be congratulated on the thoroughness with which he outlined and executed the experimental work. Following are some observations based on the data included in the papers and elsewhere. The iron nitride needles greatly increase the elastic limit of the ferrite-nitride complex. This is proved by the fact that the elastic limit of the weld material is very much higher than the elastic limit of pure

Jan 5, 1919

By R. W. Raymond

The name of Oswald J. Heinrich first appears among the members of the Institute in the first volume of its Transactions, which records that lie was elected at the Boston meeting, in February, 1873. That name has stood ever since upon our catalogue of active members. It has appeared frequently in the reports of our debates. It has been attached to many interesting and important professional papers. Henceforward it must hold a place, silent but significant, ill the pathetic lengthening list of our departed. From a present

Jan 1, 1886