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EVERY mould, of whatever kind it may be, must have an entrance appropriate to the material if it is wished to fill its inner space with bronze or other metal. It is likewise necessary that it have vents, that is, air holes, for there is nothing that is not full of air even though it be called empty. Now, molten bronze is a material that has an immediate effect because of its heaviness, and because it is as hot as fire or even hotter,

Jan 1, 1942

"WELFARE…Welfare endeavor in connection with both the metal and the coal mines of Utah has shown gratifying progress during recent years and both the operators and their employees are deserving of much credit for the efforts put forth to better living, working, educational and receational conditions in most of the mining camps of the state.In the older metal mining camps of Utah, where the towns are incorporated and independent of the mining properties operating in the vicinity, less opportunity is pre¬sented for the companies to exercise efforts looking towards improved welfare conditions than is the case of camps located on company ground and under the full control of operators.Even in such camps, however, as illustrated in Bingham, the companies can do much to better welfare conditions. In this camp the Utah Copper Company has spent $800,000 since 1 920 in the erection of modern brick cottages, apartment houses and the Gemmell Memorial Club. The cottages and apartments have every convenience to be found in up-to-date city homes. The Gemmell Memorial Club, erected and equipped at a cost of $1 75,000, was provided by the company for the benefit of the Utah Copper Company employees living in the canyon and has been made the recreational center for the camp."

Jan 1, 1925

By William P. Blake

THE magnetic iron ores of the Rees & Wilder tract, Unaka Mountains, East Tennessee, and North Carolina, so far as examined by me, are peculiar in containing considerable quantities of the mineral zircon in dark red-brown crystals, ranging in size from one-tenth of an inch, or less, to five-tenths of an inch in length. As zircons are decomposed by fusion with alkalies, the constituents may exert some favorable influence upon the iron product, which is generally acknowledged to be of superior quality. NEW HAVEN, April 20th, 1878.

Jan 1, 1879

By F. E. Gregory

MINING methods and customs in many districts of England are to this day strangely bound about by the records and traditions of the past. In some mining fields this is more apparent than in others, yet it is everywhere in evidence, for Cornwall with her mines under the sea, Wales with her famous quartzites, and Derbyshire with her remarkable cavern deposits, are all tinctured with quaint customs that have come out of the almost forgotten past. Here, modernism has never replaced tradition, and many of the laws are woven of the woof and warp of ancient custom. Indeed, these things exist because they have come to be part and parcel of the civil laws. And these laws are observed with meticulous care and accorded all the reverence due their venerable age. All activities pertaining to the mining of metals are hedged around by curious and ofttimes clumsy laws, each minute and trivial detail being covered by the civil code, and each petty law enforced by an ofttimes pompous official.

Jan 1, 1933

By Gilbert E. Doan

WHEN metallurgists and other engineers meet their college classmates or former teachers, the conversation will frequently become reminiscent and finally turn to engineering education. These graduates have tested the value of their college training in the hurly-burly of the outside world so respectful attention is due their opinions, which, strangely enough, fall into two opposite categories. A member of one group expresses a deep-seated conviction that engineers should have a fuller foundation of physical chemistry, another asks for a more thorough training in mathematics, others wish a more thorough grounding in refractories, a series of courses in petroleum engineering, or in electric welding. Each alumnus of this group

Jan 1, 1937

By Warden A. Moller

(Pittsburg Meeting, March, 1910.) THE Fushun coal-field, now being opened up by the South Manchurian Railway Co., is connected with the main line by a branch, 30 miles long, from Sui Chia Tun, 10 miles south of Mukden, the capital of Manchuria. The coal-field, which lies on the southern bank of the Hun river, 25 miles east of Mukden, consists of a long narrow valley,. running east and west between hills composed of granitic and volcanic rocks. At the foot of the northern hills, the Hun river flows westward towards the Liao river, which drains the greater part of South Manchuria. At the foot of the southern hills, resting immediately upon volcanic rocks, and overlain by 20 ft. of alluvial, is a thick layer of Tertiary shales, carrying near the base two coal-seams. In many places the lower of these two seams is in immediate contact with volcanic lauds and basalts, the flows of which were evidently both prior and subsequent to the formation of the coal-seams. This contact has practically destroyed the lower seam for commercial purposes. The value of the field lies in the upper seam, which, for a length of nearly 8 miles, varies from 100 to 130 ft. thick. Of this seam, 85 per cent is good coal. The seam dips to the north conformably with the shales, at angles of from 25° to 30°, and appears to have an uninterrupted dip for about 1.5 miles before being possibly cut o$' by the northern hills. The coal-bearing shales extend east and west for a length of about 20 miles, but towards the east the continuity of the seams is broken by intrusive rocks. The coal is of the sub-bituminous variety, low in ash, bright in appearance, and breaks with a conchoidal fracture. It has the usual qualities of Tertiary coal-quick steam-raising and poor stacking-qualities. Pieces of resin, varying in size from

Apr 1, 1910

By John Henry Harden

With imperfect instruments it is impossible to make accurate surveys; the results are inaccurate maps, with their attendant consequences. The design of the writer is to describe an improved form of tripod head, and certain defects in an English transit and a miners' dial, with the method taken to remedy the defects of the transit. When the present transit superseded the surveyor's compass, there was one special objection brought against it, and with some show of reason ; namely, that the tripod of the compass with its ball and socket motion, allowed a quicker levelling-up (and, consequently, more work) than mas possible with the transit. To this objection it was replied, that the ball and socket would not allow the instrument to be levelled with the same degree of precision that could be attained with the levelling screws, and that if time was sacrificed greater accuracy was attained. Nevertheless, it is a wellknown fact that in this country, and especially in England, the compass or miners' dial holds its ground solely from its rapid adjustment. Ever since the introduction of the transit, efforts have been made to give to this instrument the same facility of levelling possessed by the compass or dial, and the same means have been tried, i. e., a ball and socket motion, since a modification of this in some form was the only method that would answer. The upper part of a transit is, however, much heavier than the corresponding parts of a compass, and, therefore, requires more binding power, which cannot be obtained with an ordinary ball and socket joint. It has been a study with instrument-makers to combine the facility of these two tripods —the quickness of the ball and socket with the steadiness and accuracy of the screws; but in all attempts in this direction the ball and socket of the compass has been literally followed, the entire stability of the instrument depending upon the friction of the ball in its socket. There is great need for a tripod that can be more easily manipulated than the present form, for it rarely happens that an engineer has a level surface on which to set his instrument, and very often

Jan 1, 1879

By Arthur C. Simmons

The Pennsylvania-grade oil industry suffered a serious decline in 1938, which can be largely accounted for by the decrease in the use of lubricating oil. Production was considerably lower than in previous years and prices were very much lower. Operating profits undoubtedly were lower than the year 1933, for the average price of Bradford crude in 1938 was $1.898 as compared with $1.86 in 1933, and the difference in average price of $0.04 per barrel was more than offset by increased operating costs and taxes. Bradford Field Production in the Bradford field in the state of Pennsylvania averaged 36,759 bbl. per day in 1938 as compared with 41,300 bbl. in 1937. The decline in average daily production of 4541 bbl. can be attributed to low market price and pipe-line proration rather than to the actual physical capacity of the field. Pipe-line proration was in effect for the last eight months of the year and the daily average production per month fluctuated between a maximum of 41,852 bbl. per day in March 1938 and a minimum of 33,649 bbl. per day in November. Production figures for Bradford field have been corrected to include only the parts of the Bradford field that arc within the state of Pennsylvania, but the well-completion data for the Bradford field cannot be segregated and include those of the entire Bradford field, part of which is in Sew York state. Production from the Bradford field was obtained almost wholly by water-flooding and no radically new methods or practices occurred. Intensive research work was carried on both by individuals and companies and as a cpooperative enterprise, and minor improvements are gradually occurring in spacing, shooting, application of pressure and water conditions. Drilling Central and Southen Pennsylvania.—Pennsylvania production in central and southern Pennsylvania was obtained largely by air and gas repressuring together with the usual amount of natural production, and the repressuring operations in other than the Bradford field have not

Jan 1, 1939

By Arthur C. Simmons

The Pennsylvania-grade oil industry suffered a serious decline in 1938, which can be largely accounted for by the decrease in the use of lubricating oil. Production was considerably lower than in previous years and prices were very much lower. Operating profits undoubtedly were lower than the year 1933, for the average price of Bradford crude in 1938 was $1.898 as compared with $1.86 in 1933, and the difference in average price of $0.04 per barrel was more than offset by increased operating costs and taxes. Bradford Field Production in the Bradford field in the state of Pennsylvania averaged 36,759 bbl. per day in 1938 as compared with 41,300 bbl. in 1937. The decline in average daily production of 4541 bbl. can be attributed to low market price and pipe-line proration rather than to the actual physical capacity of the field. Pipe-line proration was in effect for the last eight months of the year and the daily average production per month fluctuated between a maximum of 41,852 bbl. per day in March 1938 and a minimum of 33,649 bbl. per day in November. Production figures for Bradford field have been corrected to include only the parts of the Bradford field that arc within the state of Pennsylvania, but the well-completion data for the Bradford field cannot be segregated and include those of the entire Bradford field, part of which is in Sew York state. Production from the Bradford field was obtained almost wholly by water-flooding and no radically new methods or practices occurred. Intensive research work was carried on both by individuals and companies and as a cpooperative enterprise, and minor improvements are gradually occurring in spacing, shooting, application of pressure and water conditions. Drilling Central and Southen Pennsylvania.—Pennsylvania production in central and southern Pennsylvania was obtained largely by air and gas repressuring together with the usual amount of natural production, and the repressuring operations in other than the Bradford field have not

Jan 1, 1939

By W. Hume-Rothery

IN recent interesting papers,1,2 Bardos et al. have described ternary Laves phases of the type A2(BsSi) and A4(B5Si3) where A = titanium vanadium, niobium, and so forth, and B = manganese, iron, cobalt, or nickel; other more complex formulae have also been established. In these phases, silicon plays the part of the smaller B atom of a Laves phase AB2, and the interatomic distances show that the effec- tive silicon radii lie between 1.16 and 1.21Å, and are thus very much smaller than the metallic radius of silicon for CN = 12. It does not seem to have been pointed out that these small atomic radii are almost the sape as the normal covalent radius of silicon (1.174Å). If, therefore, silicon acts as an acceptor of electrons as suggested by Bardos et al.,1 it appears to do so, not by the building up of a negatively charged silicon ion which would be large, but by the formation of what are very nearly or may be actually normal covalent bonds. Since a covalent bond contains two electrons, its formation would reduce the number of electrons available for bonding in other parts of the structure, and in this way the effect of silicon in stabilizing the o phase at high electron concentrations might be understood.

Jan 1, 1965

By Sir John Cadman

IN THE changed circumstances which now confront the world, an international open-door policy is the only way to keep pace with the world's demand for oil. You may rest assured that as far as the British Empire is concerned, American capital for the develop-ment of oil resources is welcome, and little obstruction will be found in the way to permit the use of foreign capital in the group of countries which constitute the British Empire. In the war days we worked in close cooperation and harmony, but in disbandment of the Petroleum War Service Committee, when the war ended, I feel that it left its task unfinished. In the wake of war there appeared a ghost of war-time conditions in the form of belief that Great Britain was straining to corner the petroleum resources of the world. I am certain that if the war-service committee had continued its work in the period of reconstruction the real story would be known and this sinister ghost would have long since vanished before the truth.

Jan 2, 1922

By William B. Millar

IN ONTARIO development of the gold mines is being rapidly pushed, while the intensity of the search for new mines has probably not been equaled at any time in the past. Even to outline the results of recent prospecting activity in Ontario would be a big undertaking, but it would be timely and, I hope, interesting to Institute members to review some generalities regarding the work of the prospector and then to discuss in some detail the growth of Ontario's most promising prospect area, the Swayze district, where serious mining operations are already under way. Probably no one writing about prospectors and pros¬pecting can resist hoping that his article will not reach the eyes of a certain portion of the uninformed general public and cause a further influx of "prospective prospectors" into any given area. It is somewhat mystifying how so many people reach the conclusion that prospecting is in

Jan 1, 1933

Jan 1, 1920

By H. F. Moore

AT PRESENT, I am connected with an investigation of the so-called fatigue of metals under stress. So far we have studied the more fundamental and simple case of the repeated stress, without the additional complexity of impact, which might bring in other factors. We feel that this investigation, which has been in active progress for a little over a year, has shown more conclusively than has been shown before that steel under repeated applications of stress, reversed from positive to negative, will not fail below some fairly clearly defined limiting stress that,, so far we can see, does not bear any definite relation to the ordinary elastic limit, being as large as the elastic limit in some cases and about one-half the elastic limit in others. I might be asked, first, what is fatigue. The old view is summed up "in the word "crystallization." The idea was that under repeated stress the material changed its crystalline structure. I do not know of any evidence in favor of the theory that metals materially change their crystalline structure under repeated stress. The crystals are broken under repeated stress. The second theory, advanced by Bauschinger, the German scientist, is that under repeated stress some inherent property of the material changes its elastic limit; it is an inherent property of the material, possibly some property of the amorphous cement between the crystal. The third view is that all fatigue of metals is the result of the spread of damage from little localized overstresses. I do not feel justified in stating my positive belief in the third view as against the second, but I have yet to run across a case of failure of steel or other metal, either in the laboratory or in service, that could not be explained by the gradual spread of damage from some nucleus. We have found, for example, that it is possible to subject a homogeneous steel, like Armco iron or a 0.90 per cent. carbon steel, that hag been thoroughly annealed, to one hundred million reversals f stress as high as the elastic limit of the steel with no sign of failure. We stopped the test at one hundred million because the machines Were required for other work. Forty-five days, continuous running at 1500 revolutions a minute is required to produce one hundred million repetitions. On the other hand, a complex structured steel, like a chrome-nickel steel that

Jan 6, 1921

THE man who forgot to mail the letters his wife gave him was for once justified at Tulsa, for envelopes, scratch paper and tablecloths were all in demand and through the two days of the meeting of the Petroleum Division, pencils were busy everywhere sketching out diagrams, drawing curves, figuring, or just taking notes. Those attending took the serious papers seriously, and discussion was wide-ranging but pointed. Despite the highly technical character of the papers presented, the chairmen had never to call for discussion; it was only necessary to say the paper was open for it. Both days the meetings lasted until after five in the afternoon, and it was enthusiastically voted to advance the meeting hour on Friday, in order to give more time. In all, ten papers, abstracts of which appeared in MINING AND METALLURGY for October, and copies of all but two of which were available in print, were presented in the two days, and no more could have been handled to advantage in that time. All but one of these dealt with problems of production engineering. That, the opening paper, was a general review of demand, supply and price in 1928, by Campbell Osborn, in which he argued for the price control of production and showed how the economic conditions determined development. J. Elmer Thomas presented a carefully prepared review of the same data, but came to somewhat different conclusions as to trend, and J. E. Pogue pointed out that in recent years it has been the manufacturing rather than the producing industries that have been notably profitable. These and other discussions were too long to be reported here, but will be printed in full later.

Jan 1, 1928

By Francis T. Havard

A Reply to the Discussion by Mr. Francis T. Havard of the Paper by Mr. Henry W. Edwards, which was read at the Atlantic City Meeting, February, 1.904. (Annual Meeting, February, 1905.) MR. HENRY W. EDWARDS, Grand Junction, Colo. (communication to the Secretary) :* Effect of Heat. It should be remembered that the coefficient of expansion of concrete is nearly that of iron; therefore in constructing flues the design must take account of this important detail. The cracking of flues, mentioned by Mr. Havard as having occurred at a temperature of 100° C. and above, . were possibly caused by neglecting to appreciate the extent of the expansion and contraction of the concrete. Effect of Atmospheric Moisture.-The moisture present in the atmosphere is exceedingly injurious to flues of any material, and those made of concrete are no more susceptible than of brick. My experience with flues of the Monier construction, having walls from 1.5 to 2.5 in. thick plastered upon a net-work of iron rods, was unsatisfactory from the standpoint of dura¬bility.

Mar 1, 1905

IT is not necessary to enter into a long discussion of ordinary bells, because every master carpenter or blacksmith knows how to make those levers with a crossbar that are called storks. This is nothing other than a board that has a thick and heavy head and looks more like a dolphin than a bird. This has a long tail in the form of a handle so that it makes a more powerful lever. As can be seen in every bell tower and other place where there are bells, it has, crosswise above the point where the cannon of the bell is fitted and fastened in, an iron bar which is arched and which has its two ends turned horizontally. These are made round so that they may turn easily when they are held by two steel rings or in two metal grooves or on glass pillows. In this, the more the transverse rod is arched,

Jan 1, 1942

By Harvey S. Chase

During the recent great depression in iron, little has been done in the magnetic separation of iron-ores; and previous to the present decade the art was in its infancy, so that there were few, if any, successful separators on the market, and but scanty practical data could be obtained as to the industry itself. Moreover, the recent development of the great Mesabi Bessemer beds, coincident with the intense depression in business, has discouraged active attempts to solve the problems presented in the crushing and separation of the refractory magnetites of the South. Experiments have been carried on, however, upon a practical scale in separating these ores magnetically, at the well-known Cranberry mines, in Mitchell county, N. C., with results which are encouraging. The magnetites of the Blue Ridge, in the South, have been known, and the soft ores of the region have been used in Catalan forges, since very early times. The original settlements in East Tennessee were made along the Watauga river by Daniel Boone, William Bean, John Sevier, and other stalwart pioneers; and this valley lies parallel with the " Cranberry " lead, which is undoubtedly the most celebrated and the most extensive deposit of workable magnetic ore in the Southern States. This lead I have personally traced along the outcrop, be-

Jan 1, 1896

By P. Schwed

IN determining the mechanism responsible for sintering, the most direct procedure available is the comparison of the observed time and temperature dependence of the process with the dependence to be expected upon the basis of each conceivable mechanism. This was done by Kuczynskil who, in treating the mechanism of surface diffusion, postulated, in effect, that the concentration gradient of vacancies is different from zero only within the neck. This procedure was recently questioned by Cabrera' who assumed, on the contrary, that diffusion occurs only in the region outside the neck. In the present note, the calculations are performed without restriction on the region of diffusion. To carry out this objective it is first necessary to

Jan 1, 1952

Jan 1, 1940