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By AIME AIME

INSTITUTE members attending the Annual Meeting in New York who want to see one of the mining engineers' newest aids, photoelastic stress analysis, are due for an interesting afternoon on Thursday, Feb. 15, when open house: will be held at the Columbia University mining laboratory. Information as to the direction and distribution off stresses in mine structures, which has been developed by Professor Bucky, associate professor at the Columbia School of Mines, and David Sinclair, research assistant, is useful in the design of pillars and in the placing of openings relative to working places such as gangways and haulage levels.: This work has been sponsored during the last ten years by the Engineering Foundation.. It is fully reported in T. P. No. 1140.

Jan 1, 1940

By David Cole

AT the time flotation appeared upon the metallurgical horizon in Arizona, the writer, under the direction of Dr. Ricketts, was engaged in remodeling and enlarging the No. 6 Concentration Plant of the Arizona Copper Co. at Morenci, and the work had been in progress nearly a year before the Inspiration experiments with flotation had disclosed the revolution in concentration that was at that timè impending. The simplified flowsheet worked out for the remodeling of the Morenci plant had been based upon the removal of the freed metal in a minimum number of stages by treatment upon tables equipped with Butchart riffles, the latter being adapted to accomplish both classification of feed and removal of the metal at one operation, substantially as described in my previous paper.1 The scheme of treatment for the slime was based upon the well-known fact that after copper sulphides, such as chalcocite and chalcopyrite, etc., are reduced to a certain extremely fine state of comminution they are definitely beyond the reach of separation upon any of the concentrating devices then known. By using drag-belt classifiers (which served as conveyors as well as separators), the overflow would be of the usual "slimes" class. Experiment had shown that when these drag-belt overflows were, properly diluted (that is, to about 5 to 7 per cent. solids in the feed under treatment) . the very fine sand, and especially the very fine but still granular sulphide particle's, would, if given a short distance to fall, quickly settle out in prime condition to yield an excellent recovery on vanners; a further valuable feature would be that the very fine non-separable final overflow tonnage might be discharged direct to tailing, thus conserving space requirements so as to permit within the old building, without embarrass-ment, the increase of capacity required.

Jan 9, 1916

By S. G., Lasky

IT seems to be in the nature of concepts that they have many meanings, and that the meaning best reflecting the primary interests of a person tends to be accepted by him as the normal meaning of the concept. The concept of ore reserves is no exception, for there is no unanimity of meaning among the several groups of us who are interested in ore reserves, nor even among the individuals of a single group. The groups most interested in ore reserves would seem to include at least the mining industry, perhaps State taxing agencies, and the Federal Government in all its diversified activities, and I would include also the citizenry at large or at least that part of it that consciously thinks about problems-of national welfare. To each of these, and to different individuals within them, the term reserves represents something different, and the farther away the individual or group gets from physical contact with the ore, the more abstract does his or its concept become. It is something different to the policy maker from what it is to the fact-finder or to the miner.

Jan 1, 1945

By C. E. MacQuigg

BY and large the education of the engineer has been conservative and the reasons for this are obvious. Quite properly it has been a tradition of engineering education that facts and not fancies must be adhered to. Without a doubt, those men who formed the mold of our engineering philosophy as much as it is possible for such molds to be established-rightly held the highest standards of intellectual honesty. Fortunately, it was unthinkable to them to temporize with untried theories and naturally the men whom they trained as engineering educators carry this philosophy in turn to their students, thus handing down the tradition of stability.

Jan 1, 1943

By AIME AIME

ON March 14, the University of Tulsa was accepted as a member of the North Central Association of Colleges, which ranks Tulsa among the leading universities of the country. A. G. OIiphant recently donated to the new school of petroleum engineering a splendid collection of books on geology, valued at $25,000. Waite Phillips, an oil producer and chairman of directors of The Independent Oil & Gas Co., donated $150,000 for a petroleum engineering building

Jan 1, 1929

By AIME AIME

0 N March 5, at Carnegie Hall, Cleveland, the Ohio Section held a joint meeting with the Cleveland Engineering Society, and the local sections of the American Chemical Society, American Society of Mechanical Engineers, and the American Society for Steel Treating. Prior to the meeting there was an informal dinner attended by 50 men. Then followed an address, "The Principles of Corrosion Protection," by Ulick R. Evans, the well-known British specialist in this problem. There were 266 present, presided over by Zay Jeffries, president of the American Society for Steel Treating and a member of the Cleveland Engineering Society. The address was well received and some discussion followed

Jan 1, 1929

By AIME AIME

T HE Mid-Continent Section of the Petroleum Division met on Mar. 11 in the engineer's room of the Tulsa Building, Tulsa, Okla., for the purpose of reviewing the papers presented at the annual meeting in New York. L. G. E. Pignell, chairman and delegate to New York for the Mid-Continent Section, read a brief report giving the outstanding features of the various papers that were presented. He expressed regret that more members of the Division could not be present in New York to hear the interesting papers and discussions. It was his opinion that the various remedies presented for overproduction seemed rather theoretical and impractical and he recommended that the engineers come to the aid of some of the economists in giving more practical consideration to the overproduction problem.

Jan 1, 1929

By N. A. Ziegler

THE chief difficulty in determining oxygen in steels is its tendency to form a variety of compounds. Almost every element, found as an ingredient in steels, maybe expected to be present as an oxide. Some of these oxides have widely differing properties, and consequently behave differently when attempts are made to reduce them by the vacuum fusion method. As I pointed out in a paper published in the Transactions of the A.S.S.T., Vol. 20, No. 1, many experimenters are spending considerable time and effort in attempting to deter¬mine the degree of completeness of the above reactions, and hold different opinions on the matter. In studying this subject the following table, taken from Hodgman and Lange's "Handbook of Chemistry and Physics" may be used as a guide.

Jan 1, 1933

By Arthur Glance

MINE safety is of the utmost importance to all operators and most operations have a safety organization, or safety inspector, whose job it is to be continually on the alert to detect and correct the hazards of mine operation. Reports from the Bureau of Mines show that next to roof falls, gas presents the greatest hazard in mining. The Bureau of Mines Information Circular 6680 shows that 162 explosions occurred in the United States during the five-year period ending June 30, 1932. Deaths resulting from these explosions amounted to 984, with a great many disabled and disfigured. A fatality rate of 6.07 persons shows the ex¬treme severity of this hazard to the industry. Various mine appliance companies have put on the market instruments for methane detection, which record in direct percentages the amount of methane present in the atmosphere. Unfortunately, few mining companies are using these instruments, however. Those available include the Burrell methane detector, the Wolf, the Martienssen, the Mine Safety Appliance detector, and the Union Carbide Company methane detector, which last I have used extensively in making mine inspections.

Jan 1, 1936

By E. C. IBBOTSON

THIS process was reported upon by the Canadian Commission in 1904, and much detailed information was also given in a paper by Chief Engineer V. Engelhardt.1 Believing that some of the latest particulars of the process will be of interest, I submit the following data. At Gysinge in Sweden during the year ending May 31, 1906, from a fixed furnace giving 1 ton (2,240 lb.) of steel per tap, there were produced 950 tons of tool-steel and special steel ingots. . In carbon and iron tool-steels all the usual tempers were made. The bulk of this steel was made from charges composed of about 80 per cent of Swedish white pig-iron and 20 per cent. of steel-scrap. The percentage of carbon was regulated by the addition of briquettes. Other charges were made from Swedish white iron and steel-scrap. The average time taken per charge, for the year, when adding briquettes, was 7* hr., and the electric energy consumed was 1,128 units (kilowatt-hours) per ton. The average time per charge for white-iron and scrap charges was 5.5 hr., and the electric energy consumed was 886 units per ton. These consumptions include all time and energy lost from various causes, such as bad water-supply, ice, etc. It is quite ordinary practice to complete the charges with briquettes in 6.5 hr., and without briquettes in 5 hr., as shown by the following typical charges White pig-iron, 1,457; steel-scrap, 439; briquettes, 220; ferrosilicon (50 per cent. of silicon), 17 ; ferromanganese (80 per cent. of manganese), 15 lb. ; and aluminum, 1 oz.=

Nov 1, 1906

Olof Venstrom (communication to the Secretary*):—In order to do justice to a property, once the largest producer of copper in the world, which is now being reopened, with a fair promise of again becoming important, I beg to add a few words in connection with Mr. Souder's remarks on the El Cobre copper-mines. The El Cobre copper-mines were worked by the old English

Jan 1, 1905

The world's largest steam-driven mine hoist, built by Nordberg Manufacturing Co. a half century ago, has become a major tourist attraction in Michigan's Upper Peninsula. The hoist, designed by company founder Bruno V. Nordberg, is located in the Quincy Mine Number Two, just north of Hancock. Nordberg began construction of the mammoth machine before World War I, but delayed completion until after the war. The hoist became operational in 1920 and continued running until the mine was shut down in 1931.

Jan 9, 1968

Mansfield MERRIMAN,Lehigh University, South Bethlehem, Pa. (communication to the Secretary*):—The formulas established by Mr. Campbell require the use of tables in order to take into account the influence of manganese on the tensile strength of steel. On examining these tables I find that the quantities given therein may be expressed by simple algebraic forms, so that formulas for tensile strength may be written which can be used without the help of tables. Referring to the case where the carbon is determined by

Jan 1, 1906

By Charles W. Merrill

IF we follow the threads of the mining problems, upon which I have touched, we find them all leading to one great fundamental desideratum. The people of this State, of this Nation, and of this world must be brought to a better understanding of the basic nature of our industry-must be made more mineral-minded. It is my belief 'that there is not a man present among this earnest gathering of those interested in the mining industry, who has not a deep-seated and heartfelt desire that the existing unprecedented welfare and prosperity of the whole mass of American people be maintained not merely through our own generation but through the generations of our children and their children. In the decades to come there can be no question of the keenness of the foreign competition which we are doomed to meet, and in this great international contest that Nation which has the best balanced program of development and that broadness of vision in its governmental direction, which recognizes the necessity of a sympathetic attitude toward the upbuilding of such a broad pro- gram will be the Nation which will maintain and pre- serve that welfare of all of its people.

Jan 1, 1929

By D. R. Mitchell

FOR the second consecutive year, attendance at the Coal Division sessions far exceeded exoectations. Those in charge were continually faced with problems of finding seats and space for attending members. 115 seats were set - II~ for the annual luncheon meeting of the Division and approximately 175 members showed un. Since the hotel management would not serve more than the 115 it meant that 60 members were forced to eat elsewhere. This created hard feelings with some members. How- ever, officials of the Division were not able to obtain in advance any indication of this overflow crowd, but are suggesting to the New York Office that some means other than ticket sales be adopted to obtain an estimate of Division luncheon and dinner attendance. Members could be circularized prior to he meeting or they could be checked when registering as to the events they expect to attend. Under the inspiring leadership of Cadwallader Evans, Jr., Chairman, the Coal Division had a phenomenal growth during the year. Reporting at the luncheon meeting, Newel1 Alford stated that approximately 190 new members had been obtained. A few more years of continuing increase at this rate will make the Coal Division one of the largest Divisions in the Institute.

Jan 1, 1944

By E. A. Holbrook

LOCAL yearly taxes levied on bituminous coal lands in Pennsylvania have become a cost of first importance to the coal industry of the State. In Pennsylvania there is no State tax on real estate, but local taxation of real estate furnishes the greater part of the revenue necessary for the small governmental unit, as counties, townships, boroughs, and local school, road, and poor districts. Coal in place in the ground, whether or not title thereto has been severed from ownership of the surface, is assessed as real estate and on its supposed sale or market value. There are eight classes of counties in Pennsylvania, based on population; in populous counties of the first, second and third class, assessments are made by a county board appointed by the county commissioners and are fairly uniform throughout the county. In counties of the fourth to the eighth classes inclusive, property assessments are made by property assessors elected by and for each township within a county. In these counties the board of county commissioners acts as a board of equalization and review to hear appeals. In most counties, therefore, where there is a large unmined reserve of coal, assessments on that coal vary for each township, irrespective of the fact that the coal bed is continuous under many townships.

Jan 1, 1933

By AIME AIME

NATURE was in a smiling mood on December 18, 1883. On that day, Chester Alan Fulton, the sixty-first President of the American Institute of Mining and Metallurgical Engineers, was born, and she endowed him with every good quality within her reach - looks, physique, intelligence, and character. Brought up in the valley of the Hudson River, with the mighty Palisades which make it the "Rhine of America," he has lived up to his early promise - as a man, as an engineer and as a friend.

Jan 1, 1943

Frank H. Probert, A.R.S.M., Morenci, Arizona (communication to the Secretary): The management of mines and the system of bookkeeping employed are subjects of great interest to mine-superintendents, and such papers as that of Mr. Davis callnot fail to attract attention. The Institution of Mining and Metallurgy, London, England, has done much within the last three years to promote discussion on the many systems adopted throughout the mining world; and any papers giving individual experience will benefit that class of men who are charged with the cconomical management of mining properties. It is often said that " a good mine shows a good manager," and more often that mismanagement is the chief cause of poor returns; or, as Mr. A. G. Charleton puts it, in his able paper on " Mining Accounts and Cost-Sheets,"* " accident may, and often

Jan 1, 1902

T. Kirke Rose, London, Eng. (communication to the Secretary*) :—The authors have shown that, under certain conditions, the rate of dissolution of gold by chlorine and bromine is reduced by the addition of 10 per cent. of silver to the gold, and that the action is almost stopped when the silver amounts to 30 or 40 per cent. of the alloy. Even if full recognition is given to the practical way in which the work was done, however, it is to be regretted that Prof. Hofman and Mr. Magnusou did not determine the temperature at which the experiments were carried out. From the details given, it may be inferred that the temperature was raised by chemical action by about 20' C. when 21 g. of sulphuric acid was added, and that the mixture was then slowly cooled down during the experiment. When bromine or very weak chlorine solutions were used, there could not have been any perceptible heating-action. As the action of both chlorine and bromine is aided by heat, it follows that the stronger solutions of chlorine were given an unfair advantage over the weaker solutions, and over bromine. If the temperature had been the same in each case, I do not think that the conclusions deduced by Prof. Hofman and Mr. Magnuson' would have been found to be justified. (This is speaking generally. In barrel-treatment the conditions are similar to those in the experiments.) The superior speed of bromine as compared with chlorine at equivalent strengths is not yet disproved, and the differences noted between strong and weak solutions of chlorine may have been largely a function of the temperature. Moreover, the authors used somewhat-coarse particles of gold, and did not try how far time was a factor, although it is obvi-

Jan 1, 1906

Arthur Jarman, Sydney, New South Wales, Australia (communication to the Secretary*):—All designs for modern metallurgical and chemical laboratories should provide each student's desk with a hood or cupboard for the removal of fumes, but I doubt the advisability of placing air-baths and similar apparatus close to the hot plate. It seems to me that unless the draft be exceptionally strong the fumes from ordinary wet assay work will corrode the iron-work of the fittings, in which case the baths would have to be removed to a general desk in order to lighten the work of the laboratory attendant. Since the laboratory described by Mr. White has been in use for two years, I should like to ask if any inconvenience has resulted from this corrosion. If not, it is certainly an important improvement to have the air-baths and similar apparatus placed on the student's desk. The hoods described by Mr. White are supplied with a good draft by means of a fan, which gives them a great advantage

Jan 1, 1905