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The thirty-ninth meeting of the Boston Section was held at the Engi- neers? Club on Monday evening, Dec. 4, 1916. Thirty-three members and guests sat down to dinner; There were present as section guests; Dr. L. D. Ricketts, and Prof. Bradley Stoughton, President and Secretary of the parent society, and each was called upon to speak. Mr. Stoughton spoke of the growth of the Institute during the past year and described the very numerous and important activities, of which the junction of the American Society of Civil Engineers with the other three societies is perhaps the most important. Dr. Ricketts, the advertised speaker of the evening, spoke on Recent Progress in Mining and Metallurgy of Copper Ores. In discussing the improvements in mining, he traced the mining methods from square- set mining to the modified Ohio System now so successfully used at Inspiration: In metallurgy, he described the growth of reverberatory-smelting ant1 allied problems such as the utilization of the waste heat for generating steam. He laid stress on the importance of sampling and bedding of

Jan 6, 1917

By Frank T. Weems

The basic operating properties of the DorrClone are discussed and certain metallurgical applications which exploit these properties are presented. An effective method of controlling the consistency of the DorrClone underflow is described.

Jan 8, 1951

The Wheeler Condenser & Engineering Co., of Carteret, N. J., is now building a line of horizontal and vertical shaft centrifugal pumps for general services, as well as for condenser work.. This company has been building centrifugal pumps for over 20 years, most of them being used, however, in connection with condensers. The new line of pumps is suited for all services. A small motor-driven unit for tank or stand pipe operation is shown in Fig. 1. Referring to the sectional illustration (Fig. 2), it will be seen that this pump conforms to the most recent advances in centrifugal pump construction, having a two-part divided casing, with the suction and discharge nozzles in the lower half. The impeller is of the closed double-suction type, protected by labyrinth wearing rings. The shaft is protected from the water by bronze sleeves, which screw on to the shaft and extend clear through into the bearing bracket boxes. Bearings are of the ring-oiled type, and in the outboard bracket, is a ring-oiled thrust bearing, which is a refinement not usually found in double-suction

Jan 4, 1916

ALTHOUGH it might seem more fitting to discuss this subject in the Ninth Book in connection with the smelting of iron where I had thought to treat of it in detail, this process of making steel appears to be almost a branch of the above chapter on iron itself; hence I did not wish to separate these two so far that they might seem to be [18v] different things. Therefore I wish to write of it here and to tell you that steel is nothing other than iron, well purified by means of art and given a more perfect elemental mixture and quality by the great decoction of the fire than it had before. By the attraction of some suitable substances in the things that are added to it, its natural dryness is mollified by a certain amount of moisture and it becomes whiter and more dense so that it seems almost to have been removed from its original nature. Finally, when its pores have been well dilated and softened by the strong fire and the heat has been driven out of them by the violence of the coldness of the

Jan 1, 1942

By Fritz F. Prugger, Peter R. Jones

This paper considers some of the main aspects of underground mining in the flat, rich, but deep lying deposits of Saskatchewan. It briefly describes the pertinent geological features as they relate to mining and the practical de-stressing techniques used to allow productive extraction in the high stress environment present in many of the province’s mines. Mining layouts, materials handling, and the evolution of some of the world's largest mining equipment are examined.

Jan 1, 1983

Discussion of the paper of Robert Franke, presented at the Butte meeting, August, 1913, and printed in Bulletin No. 79, July, 1913, pp. 1201 to 1205. ARTHUR 0. GATES, Lafayette, Ind. (communication to the Secretary*) :-In connection with the comparison of mechanical crushing efficiencies in Tables I and II of Mr. Franke's paper, I wish to suggest a somewhat simpler way of making this' comparison, based upon what the writer has called the "crushing-surface diagram," as published by him in the Engineering and Mining Journal for May 24, 1913. Such a diagram, based on the data given in Table II, is submitted herewith, Fig. 1, cumulative percentages being plotted as abscissas and reciprocals of diameters (theoretical mesh per inch). plotted as ordinates.. Such a diagram averages the diameters without calculation, and areas upon it are proportional to surface produced, and, in accordance with Rittinger's law, to energy spent on crushing alone.

Jan 11, 1913

By Thomas Connolly

The Homestake Mine is situated in the northern portion of the Black Hills of South Dakota in a series of steeply dipping and highly folded Precambrian Rocks. The ore bodies are localized along plunging anticlinal and synclinal folds which are locally called "ledges." The gold bearing ore is confined mainly in the Homestake formation which is an iron-magnesium carbonate series of rocks. The individual ore bodies are pipe or lense-shaped zones which plunge 30º to 75º from the horizontal. These ore bodies range from 10 to 100 feet wide and 50 to 400 feet along the strike. Gold values are erratically distributed in a gangue consisting of cummingtonite schist, sideroplesite schist, quartz, pyrrhotite, arsenopyrite, chlorite schist and ankerite. Usually the ore bodies dip at 70° to 80º and often have folded shapes like "fish hooks" or "troughs." Ore grades must be determined by extensive sampling and all mining is based on assay control.

Jan 3, 1974

By F. J. Darnell

SINGLE crystals of a-titanium are difficult to obtain because of the phase transformation at 882 °C in which the structure changes from the high-temperature body-centered structure ß to the low-temperature hexagonal close-packed structure a. Preparation of single crystals of a-titanium has previously been accomplished by a strain-anneal method which takes several days and is not generally reproducible. Single crystals as large as 5 mm

Jan 1, 1959

By Howland Bancroft

The writer has observed that some confusion is experienced by many mining engineers in making vertical sections of ore deposits in mining properties which they have examined. Having much examination work calling for the correct interpretation of vein structure and the subsequent platting of the same on sections, it has occurred to the writer that the accompanying diagram may be of use to others who at times may be called upon to prepare numerous sections. For example, a great mass of data on strike and dip of ore bodies is collected underground in separate

Jan 1, 1915

Jan 1, 1969

New York Meets first Wednesday after first Tuesday of each month. J. E. JOHNSON, JR., Chairman. EDGAR RICHARD, Vice-Chairman. D. M. LIDDELL, Secretary, 7 Wall St., New York, N. Y. C. A. BOHN, Treasurer. JOHN V. N. DORR, LEWIS W. FRANCIS. Boston Meets first Monday of each winter month. R. L. AGASSIZ, Chairman. JAMES G. CARLETON, Vice-Chairman. E. E. BUGBEE, Secretary-Treasurer, Mass. Inst. of Technology, Cambridge, Mass., W. E. C. EUSTIS. G. A. PACKARD. Columbia Holds four sessions during year. Annual meeting n September or October. W. H. LINNEY, Chairman. OSCAR LACHMUND, Vice-Chairman. LYNDON K. ARMSTRONG, Secretary-Treasurer, P. O. Drawer 2154, Spokane, Wash. STANLY A. EASTON, S. SHEDD. Puget Sound Meets second Saturday of each month SIMON H. ASH, Chairman. I. F. LAUCKS, Vice-Chairman. CHARLES SIMENSTAD, Secretary-Treasurer, 425 Lyon Bldg., Seattle, Wash. GLENVILLE A. COLLINS, JOHN N. POTT

Jan 7, 1917

By Persifor Frazer

The structure of the Caucasus as made out by the Russian geologists and represented in Pamphlet XXII. of the Livret Guide, by Loewinson-Lessing, is an overturned anticlillal from Lars to Passanour; a distorted synclinal with monoclinal dip from Passanour to near the summit of the anti-Caucasus chain south of Tiflis; and another overturned auticlinal from this point to Erivan on the Armenian border. Ng—Neogene; Pg— Paleogene ; J,—Upper Junssic (and Cretaceolls in other parts of the chain) ; J1—Lias ; Pz—Paleozoic schists plicated ; yd—massives of granite and diabase; —porphyries ; —trachytes, andesites; Pz, Mz, plicated sedimentary deposits of Armenia. The details of the geology, however, are extremely complicated—so much so, indeed, as to make it impossible for any set of men to have worked them out in a single season. For 'the structure as a whole it will be necessary, therefore, to rely implicitly upon the labors of the Russian Geological Survey, and it is intended here only to state these, and to record a few notes supplementing them. Setting out from Wladikavkaz in the early morning, we pass

Jan 1, 1899

By G. H. Clevenger

Discussion of the paper of ALLAN J. CLARK presented at the San Francisco meeting, September 1915, and printed in Bulletin No. 103, July, 1905, pp. 1381 to 1398. G. H. CLEVENGER, Palo Alto, Cal.-Since the precipitation of extremely dilute solutions as regards cyanide presents one of the greatest problems of zinc-dust precipitation, I should like to ask Mr. Clark the minimum concentration in cyanide of the solution from which it is possible to precipitate satisfactorily the gold with zinc dust in Homestake practice. A. J. CLARK.-For a day's work about 0.015 per cent. That is precipitating a very low-grade solution, very low in alkalinity. It requires probably 0.2 lb. of zinc dust to the ton. JOHN A. FULTON, Melones, Cal.-At the Melones mine, we have been working very low-grade rock for a number of years, the process being amalgamation and concentration up to the last year. The value of the ore increased so that we had to supplement the concentration with a sand and slime plant. Classification was a problem, since to install classifiers would mean tearing the mill all to pieces. We are therefore making use of a Wilfley table for this purpose. The amount of wash water is increased and a stream of fresh water is also run into the feed box at the

Jan 12, 1915

By Kenneth W. Luke

A computer programing system has been devised to assist in open pit mine design planning. This system operates upon data generated for cross sections in the mine plan, and parallels present manual methods used in mine design, resulting in a minimal communications barrier between the mine planner and the computer. Input data for each cross section includes geologic interpretation and mine design parameters such as wall angles, bench heights, berm widths, and ramping system. The program will optimize the design of each cross section to give minimum stripping at any desired ore reserve level. This system is functional in the sense that it is easily adopted, changes in mine design parameters can be quickly evaluated, and each resultant design incorporates all recognized mining constraints.

Jan 1, 1973

By W. H. Gauvin, N. J. Themelis

Jan 1, 1963

By Chi-Yuen Wang, Chaw-Long Chu

The time-dependent volumetric constitutive relation for a San Andreas fault gouge and a consolidated kaolinite are experimentally determined at confining pressures to 200 Mpa, under creep condition and at ultrasonic frequency. At any given pressure, the bulk modulus determined at 1 Mhz frequency is identical to the "elastic" modulus determined at a stepwise change of pressure. After the pressure change, there occur a time-dependent change of volume and thus the effective bulk modulus. The constitutive relations may be modeled by a standard linear viscoelastic medium with pressure-dependent moduli and viscosity. For the San Andreas fault gouge, viscosity increases from 2x10 13 poise, at 17 Mpa, and 10 14 poise, at 100 Mpa. For kaolinite sample, the corresponding values are 3x10 12 poise and 10 13 poise. These results imply that both stress and pore pressure in fault zones may show time-dependent variations in response to a change of state of stress, such as that occurring after an earthquake.

Jan 1, 1982

By Ossi V. I. Hintikka, Andrew Balint

Sorting tests on limestone at the Lohjan Kalkkitehdas Oy Ojamo mine, Finland, are described. The tests, conducted to evaluate a Sortex 811MW optical separator, were successful, and upon completion, the sorting machine was put into production. Optical separation characteristics of the limestone, used for cement manufacturing, are described. Problems of winter operation are discussed. Operating costs are given.

Jan 1, 1972

Discussion of the paper of R. H. RICHARDS and BOYD DUDLEY, JR., presented at the New York meeting, February, 1915, and printed in Bulletin No. 97, January, 191.5, pp. 67 to 72. R. H. RICHARDS, Boston, Mass.-I believe that the manner of working for efficiency in almost all lines is to study the conditions of highest efficiency, and then to measure what is being clone. We can then see how near we have approached the highest efficiency. Spigots in practice often use many times the water theoretically needed. There are places where that is necessary for safety reasons. There are, however, places where it is unnecessary, and in these places it seems to me that this work of Mr. Dudley's will be a great help to the mill man to arrive at the greatest economy of water and highest efficiency. ALBERT R. LEDOUX, New York, N. Y.-A good many years ago I received a telegram from that distinguished engineer, Hamilton Smith, which simply said in substance: "I have discovered that liquids will flow faster from a square orifice than from a round orifice of the same area, under the same head." I wondered why he sent me the telegram, but some time afterward he told me that he had been making experiments along that line in Montana; that he thought the discovery was interesting

Jan 5, 1915

The conservation movement, initiated during the time of Gifford Pinchot and Theodore Roosevelt, has gradually taken hold of the popular imagination of the American people; and today, although it is little understood, it is an accepted doctrine. But the subject should not degenerate into cheap and misleading publicity. In the wise development and use of human and material resources lies the answer (Fig. 4). Conservation does not mean the parsimonious and misguided avarice of the miser, but the prudent and intelligent use of all types of resources, and the opening of a way for the use of those potentialities that lie just beyond the horizon and wait for man's constructive efforts to make them available. Conservation consists essentially in not emptying the pools of primary wealth before the minds of men, guided by ingenious research, have found ways to replenish them from sources as yet untapped. To advance successfully along this path, man should be guided by science and by a decent understanding of his obligations to his fellow man and particularly to his children and his children's children. Two pathways branch from this general road. One is the restraining of those spendthrifts who would throw away our national heritage for the sake of a cheap and irresponsible enjoyment of the present. Conservation in the generally understood sense usually has meant

Jan 1, 1950

By Gail Moulton

THE oilfields in Illinois are located principally along the LaSalle anti-cline in the southeastern part of the state. The oil produced comes most largely from beds of Pennsylvanian and Mississippian age, but there is an increasing important production from deeper horizons, as will be noted under new development. The oil is largely of paraffine base, and has an average specific gravity of about 35° Baume. The rank of Illinois as an oil producer has dropped from third since 1913, when its production was exceeded only by that of California and Oklahoma, to eighth in 1923. This has been the result of failure to find new pools of considerable size to offset the declining production of the old wells and of the greatly increased production of some of the other states. The noteworthy features of petroleum production in Illinois during 1924 are: the low rate of decline for the state as a whole; the smaller percentage of dry holes; and the larger average initial yield of the new wells.

Jan 3, 1925