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BOSTON LOCAL SECTION Executive Committee HENRY L. SMYTH, Chairman ALFRED C. LANE, Vice-Chairman AUGUSTUS H. EUSTIS, Secretary-Treasurer, 131 State St., Boston, Mass. ROBERT H. RICHARDS ALBERT SAUVEUR Meets on the first Monday evening of each winter month, Twenty-third Meeting The Twenty-third Meeting of the Boston Local Section was held at the Engineers' Club, 2 Commonwealth Ave., on Monday evening, Nov. 30,- 1914. Prof. R. A. Daly addressed the meeting on The Iron Ores of Küruna; Sweden. AUGUSTUS H. EUSTIS Secretary.

Jan 1, 1915

ST. LOUIS SECTION EUGENE MCAULIFFE, Chairman, J. N. HOUSER, Vice-chairman, VICTOR RAKOWSKY, Vice-chairman., H. G. WASHBURN, Vice-Chairman, W. E. MCCOURT, Sec'y-Treas., Washington University, St. Louis, Mo. H. A. BUEHLER, G. H. COx, L. C. GLENN, E. A. HOLBROOK, W. E. NEWNAM. The eighth meeting of the St. Louis Section was held at the Mercantile Club on Apr. 15, 1918. ,, The meeting was preceded by a dinner, at which 51 members and guests were present, and at which T. T. Brewster presided. Bradley Stoughton, Secretary of the Institute, and Major J. R. Fordyce were the guests of the Section. A number' of the Joplin members were obliged to leave before the close of the dinner, in order to make train connections. The Vice, chairman, therefore, called on Victor Rakowsky, who brought a message of greeting from the Southwest district. At the close of the dinner, the Vice-chairman, T. T. Brewster, introduced Bradley Stoughton, who talked on various subjects of interest to members of the Institute, especially the affiliation of local sections with those of other national engineering societies. The minutes of previous meetings were read and approved-and-the Treasurer presented a financial report covering the previous year.

Jan 6, 1918

CHICAGO SECTION CHARLES H. MACDOWELL, Chairman, Luther V. DICE, Vice-Chairman, HENRY WT. NICHOLS,. Secretary-Treasurer, 164.5 E. 68 St., Chicago; Ill. ALEXANDER K. HAMILTON-, HENRY P. HOWLAND, GEORGE P. HULST, FREDERICK 1. SNYDER. There were 32 members present at the dinner of the Chicago Section which was held at the Chicago Engineers' Club on Friday Evening, December 22. At the meeting after the dinner, the Chairman called attention to the work of Mr. Hoover in Belgium and spoke briefly of the assistance which' could be given him through the Belgian Kiddies, Ltd. Mr. Alonzo Kinyon read a paper on "Burring Powdered Coal" which so interested the members that many of them participated in the long discussion which followed. Prof. Harry B. Pulsifier then described the metallurgical plants about Chicago. He mentioned briefly the equipment and interesting features of 30 metallurgical plants of importance and stated that there were also 200 foundries in the district. He said that when number, size, quality and diversity of the plants are considered, the Chicago District is justified in calling itself the greatest metallurgical center on earth. The paper was followed by a brief discussion in Which attention was called to some smaller and incipient plants of an interesting character. HENRY T. NICHOLS, Secretary.

Jan 2, 1917

BOSTON. SECTION W. E. C. EUSTIS, Chairman, H. L. AGASSIZ, Vice-Chairman., E. E. BUGBEE, Secretary-Treasurer, Mass. Inst. of Technology, Boston, Mass. ALBERT SAUVEUR, H. L. SMYTH. The 37th meeting of the Boston Section was held at the Engineers' Club, on Monday evening, Oct. 2, 1916. Fourteen members and guests attended the dinner. The Society was fortunate in having present not only the announced speaker, J. G. Carleton of Marblehead, Mass., but also a brother member from afar, Thomas Warner of California. Mr. Carleton, who has spent the' past few years in South America, gave an informal talk on the mining of the precious metals on the South American continent. He drew a comparison of the geographical distribution of the precious metals in North and South America and pointed, out the similarity in the geological occurrence of the eastern mining, regions, mentioning particularly Venezuela and Brazil. He also directed attention to the fact that the great placers of the northwestern part of North America had their counterpart in the gold-bearing region of Columbia. The marked contrast between the southern end of North America, so rich in metals, and the southern part of South America, so poor in mineral deposits, was clearly brought out. It is difficult to avoid the conclusion that the South American Cordillera is less intensely mineralized, than the corresponding mountain.

Jan 1, 1917

By Thomas Fraser, David R. Mitchell

THE primary purpose of the loading plant is to transfer the finished product from the preparation machines to the railroad car, truck, or barge in which it is to go to market. Secondary purposes of the loading plant are: to prevent excessive degradation of sizes during loading, to reduce segregation as much as possible, and to prevent excessive quantities of very good or off-grade coal from entering any one car. Nonuniformity of consignments is one of the chief sources of com- plaints by consumers and coal merchants. A properly designed loading plant will do much to reduce complaints and ensure uniformity, not only from shipment to shipment but also in each individual consignment along the length of the car and in cross section. DEGRADATION IN STORAGE, LOADING AND SHIPMENT The object in loading is not only to handle the coal without breakage and segregation, but also to produce a well-trimmed load that will ride to its destination without spillage or breakage en route. The small sizes present in a car of prepared coal as received by the purchaser consist-of: missed small sizes not screened out in the preparation plant, breakage during loading, and breakage caused by handling en route. For domestic sizes of anthracite shipped from the Pennsylvania anthracite field to Atlantic coast cities, the dealers' lass because of breakage in loading and shipment amounts to from 2 to 5 per cent and for anthracite shipped to Middle West cities, the loss is 8 to 9 per cent. This difference is in part because dealers in the Middle West rescreen their coal more thoroughly than is usual in the East. One dealer handling Illinois No. 6 coal shipped from southern Illinois mines to Chicago reports an average size loss of 10 per cent when lump coal is unloaded with a fork. This runs as low as 5 per cent for carefully loaded coal and as high as 15 per cent for carelessly loaded coal.

Jan 1, 1943

BOSTON SECTION ALFRED C. LANE, Chairman, GEORGE A. PACKARD, Vice-chairman, H. M. BOYLSTON, Secretary-Treasurer, R. L. AGASSIZ, FRED W. DENTON. The forty-ninth meeting of the Boston Section was held at the Boston City Club on Monday evening, Dec. 23, 1918. The meeting was preceded by an informal dinner at which 29 members and guests were present; three or four others came in later. The reading of the minutes of the previous meeting was dispensed with by consent.

Jan 2, 1919

MONDAY, FEB. 17 9.00 A.M. to 9.00 P.M. Registration at Institute Headquarters. 9.00 A.M. Meeting of Committee on Development of the Activities of the Institute, Room 905, 9th Floor. 10.00 A.M. Simultaneous Sessions of Institute of Metals Division, Room 2, 5th floor. Industrial Organization, Room 1, 5th Floor. 12.30 P.M. Luncheon at Headquarters, 5th Floor. 2.00 P.M. to 4.25 P.M. Simultaneous Sessions of Institute of Metals Division, Room 2, 5th Floor. Industrial Organization, Room 1, 5th Floor. Petroleum and Gas, Room 905, .9th Floor. 2.30 P.M. Sightseeing trip by automobile for the ladies. Among the points visited will be: The American Museum of Natural History. The Episcopal Cathedral of St. John the Devine. The Spanish Museum. The American Geographical Society. The American Numismatic Society. The visits will be followed by Tea. 4.30 P.M. Memorial Service to Dr. Rossiter W. Raymond, Auditorium. 8.30 P.M. Smoker, 5th.floor.

Jan 2, 1919

National Steel Shuts Weirton Coal Operation Dutch Firm May Aid Ungava Project

Jan 7, 1953

By C. G. Rhodes, D. Kramer

High-field critical transport current density (J) measurements at 4.2 °K as a Junction of applied magnetic field (H) were made on samples of cold-rolled and annealed columbium with H parallel to J. Microscopic examination of the samples revealed a well-defined planar fiber structure produced by the cold rolling. J was found to he lower when fibers are parallel to the direction of magnetic field penetration than when they are perpendicular. This effect may he a consequence of the interaction of flux movement with fiber boundaries. THE severe changes in microstructure brought about by cold working superconductors leads to profound changes in their superconducting behavior. In particular, the ability of a superconductor to carry a transport current with zero resistance (the maximum value of this current density will be called "J" in the presence of large external magnetic fields (to be referred to as "H") is greatly influenced by the microstructure. In the case of columbium, LeBlanc and Little1 and Autler et a1.2 have observed an increase in J due to cold work. LeBlanc and Little also observed an anisotropy in J in cold-rolled columbium strips, which Hake et al.3-6 have shown to depend upon the angle between H (H ? J) and the rolling plane. An increase in J due to cold work has been found in a variety of high-field superconducting alloys3'4'7-9 as has the anisotropy effect.10 First explanations of why cold work raised J invoked the idea that dislocations carried the high-field supercurrents,8,11 since cold working drastically increases the dislocation density and presumably the number of supercurrent paths. However, recent ideas on the nature of high-field superconductivity together with new experimental evidence reveal that the bulk of certain superconductors can remain superconducting in high fields while carrying high transport currents. These later developments have been discussed by Berlin-court and Hake12 and a comprehensive review has been prepared by Berlincourt.13 According to the ideas of Gorter14 and Anderson,15 one would expect that the influence of microstructure on high-field supercurrent density will depend on tine interaction between microstructure and penetrating flux and on the direction of the Lorentz

Jan 1, 1965

By Walter Crooke

Regenerative hot-blast stoves are now in general use in all parts of the world, and are so well understood and appreciated, that I need not take up your time with an account of their history and introduction into the United States. My object in writing this paper is to give you a short description of a stove that is now being very favorably received and adopted here (see drawing). The stove was first introduced into this country in 1887 by M'Clure & Shuler (now M'Clure & Amsler), who have the management of the patent right in the United States. The English design had to be modified to suit the exigencies of American blast-furnace practice, which, in many respects, widely differs from our English experience. In the first place, the fire-bricks used in America expand to an extent unknown in England, and it became necessary to make special provision for this by increasing the number of cross-walls, and by leaving a space at the top of the stove through which the lining could expand. The expansion laterally was, however, more difficult to provide for, as the combustion-chamber in the center, being the hottest part of the stove, must necessarily expand more than the outer walls, and therefore tend to squeeze up the flue-openings. On first introducing these stoves to American ironmasters, a feel ing seemed to prevail that a " four-pass " stove did not utilize the whole of its surface. They also had an idea that the " two-pass " stove let the burning gas go before all the duty had been extracted from it; so that it was found neceseary to design a stove of a special character to suit their wishes. Hence the "three-pass" chimney top stove now before your notice, the advantage claimed for which is that each stove is independent, requiring no underground chimney flue or stack, and can be erected at a very light cost. The working of these stoves has proved to be very successful wherever they have been introduced.

Jan 1, 1891

PRESIDENT BENJAMIN B. THAYER, NEW YORK, N. Y. PAST PRESIDENTS JAMES F. KEMP, NEW YORK, N. Y. CHARLES F. RAND, NEW YORK, N. Y. FIRST VICE-PRESIDENT SIDNEY J. JENNINGS, NEW YORK, N. Y. TREASURER GEORGE C. STONE, NEW YORK, N. Y.

Jan 1, 1917

By R. HAYDEN, H. B. HALLOWELL, H. O. Hofman

THE object of refining copper in the reverberatory furnace is to obtain a metal which will have the highest attainable degree of malleability, ductility and electric conductivity, and present at the same time a level surface when it solidifies in the mold after casting. These desirable physical properties are governed by the character of the impurities and the forms in which they are present, by the amount of cuprous oxide retained by the copper, by the quantity of gas held in solid solution, by the casting-temperature, and by the thickness of the casting. The effects of impurities, of cuprous oxide and of gases upon the mechanical properties of copper have been studied by Hampe in his classical paper "Contributions to the Metallurgy of Copper." The most recent research into the effect of metals upon the electrical conductivity of copper is that of Addicks.2 The influence of cuprous oxide upon the electrical conductivity has been investigated by Walker' and Addicks.4 The absorption of gases has received' attention by Hampe,5 Stahl 6 and Heyn.7 The effects of casting-temperature have been noted by Stahl.8

Mar 1, 1907

By Carl Scholz

DURING November And December, 1907, Four Serious Mine-explosions Occurred In The Appalachian Coal-Field, Which Resulted In The Loss Of Nearly A Thousand Lives And Caused An Enormous . Damage To Property. These Accidents Attracted More Than The Usual Attention; Coal-Trade And Engineering Papers Contained Many Comments And Suggestions On The Cause And Prevention Of Accidents; The Daily Press In Many Instances Condemned The Coal-Operators And Charged These Accidents To Their Negligence, Or Their Anxiety To Make Money Without Adopting Precautionary Measures. Immediately After Each Accident The Respective State ..Authorities Ordered Close Investigations To Be Made, With The View Of Establishing The Cause And Suggesting Remedies To Prevent Recurrence. Representatives Of The Technologic Branch Of The U. S. Geological Survey, To Whom The Investigation Of Mine-Accidents Had Recently Been Delegated By The Secretary Of The Interior,. Visited The Mines And Co-Operated With The Local Authorities In Their Determinations. It May Be Safe To Say Here That An Investigation Of A Mine After An Explosion Has Occurred Discloses But Little, Because. The Causes Have Been Removed And Conditions Have Been Entirely Changed. On Jan. 8, 1905, The Coal-Operators Of West Virginia Organized An Association At Washington For The Purpose Of Making Extensive Investigations, And Sufficient Funds Were Pledged To Carry Out This Work. At This Organization Meeting, The Representatives Of The Geological Survey Present Had No Suggestions To Offer As To The Cause Of These Accidents. An Examination Of The Various Reports Concerning These Accidents Indicates That The Explosions Were Caused By The Ignition Of Gas Or Dust; They Show The Point Of Origin And The Direction In Which The Force Was Expended, And Give A Detailed Description Of The Damage Done. Very Little Has Been Said As To What

Jan 7, 1908

By W. V. Vietti, E. P. Hayes

OpeRations on the Texas Gulf Coast during 1936 increased materially over 1935. A number of new fields were discovered and a few of the older fields were extended, both by the discovery of deeper pay sands and by lateral expansion of the known producing horizons. Twenty-seven new fields have been discovered, of which 25 are oil fields and the others are gas fields that have every indication of becoming oil-producing areas. Amelia, Anahuac, Bay City, North Pettus, Placedo, Pickett Ridge and Tomoconnor have had major extensions. Production for 1936 amounted to 91,224,844 bbl., an increase of 21,627,033 bbl., or 31 per cent, over the 1935 production of 69,597,811 bbl. The number of producing wells at the end of 1936 was 6727, as compared with 4851 at the end of 1935. Proration has continued in force, thus decreasing the rate of depletion and the number of abandonments normally expected. New Fields A brief discussion of the new fields follows, in addition to Tables 1 and 2, which contain the general data on these fields. Aransas (McCampbell).-Buckingham and McCampbell No. 1 McCampbell was drilled to 7501 ft., then plugged back to 6560 ft. and completed in the Marginulina for a 100-bbl. flowing well on July 18. Bee County.—The Voss field, discovered by Swiger and Devonian's No. 1 Voss, and the Holzmark field, discovered by Miller and Donzis on the Holzmark farm, are both of the same type structurally and are caused by folding against a fault, one field being on one side of a fault and the other on the opposite side of the same fault. Brooks County.—-Standard Oil Company of Texas Garcia No. 1, the discovery well in the Alta Mew field, and Dick Young's Singer No. 1, the discovery well of Alta Verde, appear to indicate small fields. Garcia No. 1 was drilled to 8022 ft. and plugged back to 2485 ft., at which depth the well made 189 barrels. Lockridge.—This gas field was discovered by Gulf Production Company's Fairfield No. 1, in Brazoria County. It was originally drilled to

Jan 1, 1937

F A. THOMSON, president of the Montana School of Mines, gave an interesting talk on mining schools of the past, present and his ideas of the future before a recent meeting of the Montana Section of the A. I. M. E. He covered the history .of the various mining schools and com- pared the three main types of schools; those attached to or forming part of an endowed college or university such, for example, as' the Columbia School of Mines, the Mining Department of the Massachusetts Institute of Technology and the Mining Department of Stanford University. These resemble in a general way the second class, those attached to the state universities and colleges. The schools of this general type have had varied success.

Jan 1, 1928

By M. J. Saarivirta

A high-purity copper-zirconium alloy system was imesti-gated. The zirconium content of the alloys studied varied from 0.003 to 0.23 pet. The solid solubility of zirconium in copper and some physical and mechanical properties of the alloys have been determined. By proper heat treatment, Cu-Zr alloy can develop a high electrical conductivity and resistance to softening at temperatures up to 500°C (930°F). This combination of desirable properties makes this alloy superior, to other com-merzcrrl copper base alloys for- use in the electrical conductor field. DEMAND for high conductivity copper alloys that retain their mechanical properties at elevated temperatures is growing rapidly. At present, copper-base alloys such as copper-silver and copper-chromium are used where these characteristics are required. As an example, commutators in electric motors are often made of these alloys. However, the life at elevated temperature of commutators made of copper-silver alloys is much shorter than the life of the same part made of copper-chromium and copper-zirconium alloys. Copper-silver alloys are subject to creep and subsequent failure when the service temperature exceeds several hundred degrees centigrade. Use of copper-chromium alloys has been known for the past several years, but little information is available in the literature concerning the properties of alloys in the copper-zirconium alloy system. Some work had been directed toward determining the solubility of zirconium in copper as well as determining properties of the Cu-Zr alloys. These investigations have revealed the superior high-temperature and electrical conductivity properties of copper-zirconium alloys over copper-chromium alloys. The United States Metals Refining Co., Carteret, N. J. has recently produced OFHC R copper-zirconium alloys for experimentation and evaluation. Because OFHC R copper contains no appreciable oxygen, no harmful oxides are formed and the full benefit of Zr as an alloying addition is obtained. This paper describes the results of this work. It contains room-temperature and some high-temperature data which have been obtained after various processing techniaues. Actual elevated temperature properties are being determined and will be reported in a separate paper. Preliminary results obtained at elevated temperatures suggest that the Cu-Zr alloy is superior to other high conductivity copper-base alloys. WORK PROCEDURE The high-purity oxygen free (OFHC R) copper-zirconium alloys with zirconium content ranging from 0.003 to 0.23 pct were cast into 4-by 4-in. wirebars by both continuous casting and conventional casting methods. Zr was added in the form of a master alloy containing 30 pct Zr and 70 pct Cu. Castings were analyzed for zirconium and nine bars containing various amounts of zirconium were selected for this study. The results of analyses and the sample numbers are given in Table I. Typical analyses of OFHC R copper are also shown. The following properties were studied: A) Solid solubility of zirconium in copper. B) Effect of zirconium on properties of copper. C) Effect of combined working and heat treating on properties of Cu-Zr alloys. The solid solubility of zirconium in copper was determined by metallographic techniques. Specimens for this phase of the investigation were hot rolled at 900oC (1650oF) to 0.250-in. rod. The rolled rods were cut into 2/3-in. long specimens and solution annealed at 950 °C (1740°F), 980°C (1795 °F). and 1020 °C (1870 °F) for 6 hr and quenched in water. In order to find the solid solubility limits at lower temperatures, the homogenized specimens were reheated at various temperatures for 1 hr and quenched. The physical and mechanical properties were determined on 0.250 in. rod, 0.132- and 0.081-in. wires. The wires were cold drawn from the 0.250-in. rods after they were solution annealed at 980 °C (1795°F) and quenched in cold water. Mechanical and electrical properties were determined on cold drawn and

Jan 1, 1961

By Raymond E. Byler

THE challenge of unprecedented need for more metals to meet present-day re-armament and domestic requirements is being met with minerals beneficiation projects of great number and variety, and with new and improved methods, techniques, and. equipment. Iron Range Developments Much attention has been given during the year to the tremendous program for beneficiation of taconites and intermediate iron ores which is progressing through large pilot-plant tests preparatory to full-scale production operations. The greatest activity has been directed toward concentration of magnetic taconites on the Mesabi Range. The Reserve Mining Co. has let $75 million in construction contracts for the 2 ½ million-ton-per-yr project (concentrates) at Beaver Bay, Minn., and is building a 300,000-ton-per-yr pilot plant to prove up the magnetic separation and pelletizing operations. Oliver Iron Mining Co. has a pilot plant under construction near Mountain Iron for concentrating magnetic taconites, and is operating experimentally a sintering and nodulizing plant on fine ore screenings and concentrates at Virginia to fully develop agglomeration technique. The Erie Mining Co. plant at Aurora continues its production of concentrates from magnetic taconites which was begun three years ago. No plans have been announced to treat the Mesabi Range nonmagnetic taconites, but F. D. Devaney, Pickands Mather and Co., is studying a new process for magnetically roasting lean ores to make them amenable to low-intensity magnetic concentration. W. R. Van Slyke, Cleveland-Cliffs Iron Co., calls attention to several noteworthy developments in the field of intermediate ores, perhaps the most significant of which has been the first commercial operation of a Dutch State Mines (DSM) cyclone plant at the Buckeye mine of the M. A. Hanna Co. The plant concentrates the +1/4 in. fraction by means of conventional heavy-media treatment after suitable crushing, screening, and washing. The -1/4 in. +65 mesh material is treated in two 12-in. cyclones, the -65 mesh fraction being sent to tailing storage. The plant is operating successfully on feed rates up to 120 tons per hr, and indicates that successful treatment of the fine fractions of Mesabi intermediate ores is imminent. Another commercial-size DSM plant was placed in operation late in the year by Cleveland-Cliffs at the Holman mine, and two additional ones are expected to be in operation next year. Various other methods are also in use at different plants for treatment of the fine fractions, including classification, abrasion milling followed by classification, jigging, and Humphrey spirals. Where it can be economically justified, it seems at present that heavy-media treatment of the -1/4 in. fine fraction will also come into increasing use on the intermediate ores. During 1951 a one-unit, heavy-media plant to treat hematitic crude ore was erected at the Ohio mine on the Marquette Range by Cleveland-Cliffs and plans for another plant at Humboldt to produce 2000 tons of concentrates annually is contemplated, as is also the construction of a plant for agglomera-

Jan 1, 1952

By J. W. Cunningham, M. J. Stultzman

THE demand for improved materials for high-temperature service has increased during the last few years. Iron,- nickel,- and cobalt-base alloys have been investigated extensively and many alloys with outs'tanding high-temperature strength have been developed. Considerable research has been directed toward improved methods of processing these alloys. The vacuum furnace as a tool for the purification and improved control of high-temperature alloys has been studied extensively and production units are in operation. The research covered by this paper studied the effects of casting in air, vacuum, or argon upon the elevated-temperature properties of two nickel- and two cobalt-base alloys. The alloys investigated were Stellite 31, He 1049, Udimet 500, and Guy Alloy. MELTING AND CASTING PROCEDURES Two heats of each of the four alloys under investigation were melted and investment cast under the following conditions: 1) Stellite 31 was melted and investment cast in air and in vacuum, with an argon atmosphere for pouring. 2) He 1049 was melted and investment cast in air and in vacuum, with an argon atmosphere for pouring. 3) Udimet 500 was melted and investment cast in vacuum with and without additions of zirconium and boron. 4) Guy Alloy was melted and investment cast in vacuum and in argon. The heats were all melted in induction furnaces equipped with preformed magnesia crucibles of 50-lb capacity. The air-melting furnace was powered by a spark-gap converter of 40 kw capacity. The vacuum-melting furnace was powered by a motor-generator set of 100 kw capacity. The argon heat of Guy alloy was melted in the vacuum melting furnace under an argon atmosphere. Virgin materials were used for preparing all heats except the air heats of Stellite 31 and He 1049. The charge for the air heat of Stellite 31 was a commercial blend of shot. The charge for the air heat of He 1049 was Stellite 6 shot plus those virgin materials necessary to give the desired composition. All of the materials used were of the same grade used com-

Jan 1, 1960

By Jay J. Burns

TWO zinc concentrating mills are operated by the St. Joseph Lead Co. in St. Lawrence County, N. Y. The Edwards mill is operating at present only sixteen hours a day treating 400 tons daily. The metallurgy at Edwards presents no unusual problems therefore this discussion is mainly limited to the metallurgy of the Balmat ore. The Balmat mill has a capacity of 1,250 tons per day and the operating crew consists of three shift bosses each with five millmen per shift. Two crusher operators work on each of two shifts and one cleanup man on day shift. The repair crew is made up of a foreman and three repairmen, one of the repairmen being capable of taking over any operating job in the mill from shift boss down. Each millman is capable of handling the next job in line and several men in the yard crew are broken into handling the start-off job in the mill so that temporary shortages of men do not cause extensive overtime. Sphalerite, pyrite, and galena, the principal ore minerals, occur in a gangue of calcite, dolomite, and silicates, especially diopside, plus tremo-

Jan 1, 1947

Arizona E. P. MATHEWSON, Chairman F. W. MACLENNAN, First Vice-chairman CLYDE E. WEED, Second Vice-chairman E. D. GARDNER, Secretary-Treasurer Box 4097, University Station, Tucson, Ariz. I. H. BARKDOLL HENRY F. EASTER MICHAEL CURLEY R. D. LEISK Boston Meets first Monday each month, October to May, inclusive ROBERT S. WILLIAMS, Chairman GLEN F. JENKS, Vice-chairman F. LEROY FOSTER. Secretary-Treasurer Rooms 6-202, Mass. Inst. of Tech., Cambridge, Mass. HOLCOMB J. BROWN ESPER S. LARSEN

Jan 1, 1936