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By C. F. Tolman

Discussion of the paper of C. F. TOLMAN, JR., presented at the New York meeting, February, 1916, and printed in Bulletin No. 110, February, 1916, pp. 401 to 433. Louis C. GRATON, Cambridge, Mass.-Of particular interest at this time is any paper that deals with chalcocite, the characteristic product of secondary enrichment and the copper mineral of greatest commercial importance, and that seeks to aid in the distinction between primary and secondary chalcocite-a distinction of much scientific and practical importance but one which thus far it has proved difficult to draw. The present paper on this subject by Professor Tolman, like the ,many preceding it which he and his colleagues at Stanford have published in the last couple of years, contains much of interest and suggestiveness. Without endeavoring at this time to review or comment upon Professor Tolman's conclusions in detail, I may say that many of them are in accord with the findings that my associates and I have been accumulating in the course of studying secondary enrichment in many of the copper deposits of the country. On the other hand, it goes without saying that in this comparatively new field of research or, at least, a field in which

Jan 5, 1916

By R. P. Carreker

THE experiments described in this report were conducted as a part of a general program designed to document the deformation behavior of pure metals over a wide range of temperature. Material The silver used in this investigation was obtained from the Handy and Harmon Co. as 99.97+ pct pure. It is from the same length of wire as that designated H-H silver by Hoffman and Turnbull in their investigation of self-diffusion in silver.' The silver was drawn at room temperature from 0.060-in. diam to 0.020-in. diam wire without intermediate annealing. Seven-inch lengths of cold-drawn wire were annealed in groups of ten by placing them in individual quartz tubes spaced circumferentially about and near the vertical furnace axis. Dry nitrogen was passed through the furnace to lower the partial pressure of oxygen. The three annealing temperatures used were 700°, 800°, and 900°C, producing grain sizes of 0.017, 0.040, and 0.250 mm diam after 30 min at temperature. Testing Procedure The details of the testing procedure have been described in the reporting of results of a similar investigation of Copper. Annealed specimens of 5-in. gage length were gripped between grooved plates. Tests were performed using an Instron tensile-test-

Jan 1, 1958

By Brandon H. Grove

The rapid development of the Budafa-Puszta field during 1938 advanced Hungary a considerable distance along the road to self-sufficiency in domestic crude-oil supplies. Seven wells were completed in the field during the year, at depths averaging 4100 ft., and there have been no dry holes. Initial productions have ranged from 150 to about 400 bbl. per day. At the end of the year daily average production amounted to about 1400 bbl., which is equivalent to 33 per cent of Hungary's daily internal consumption. Production increased somewhat in the Government-controlled oil field at Bükkszek, also discovered in 1937, but nothing occurred to alter previous indications that this field would be capable of only relatively insignificant development. A further test of the Miocene-Oligorcene basin containing the Bükkszek field is being made by a well now drilling

Jan 1, 1939

By Brandon H. Grove

The rapid development of the Budafa-Puszta field during 1938 advanced Hungary a considerable distance along the road to self-sufficiency in domestic crude-oil supplies. Seven wells were completed in the field during the year, at depths averaging 4100 ft., and there have been no dry holes. Initial productions have ranged from 150 to about 400 bbl. per day. At the end of the year daily average production amounted to about 1400 bbl., which is equivalent to 33 per cent of Hungary's daily internal consumption. Production increased somewhat in the Government-controlled oil field at Bükkszek, also discovered in 1937, but nothing occurred to alter previous indications that this field would be capable of only relatively insignificant development. A further test of the Miocene-Oligorcene basin containing the Bükkszek field is being made by a well now drilling

Jan 1, 1939

The first meeting of the Naval Consulting Board was held at the office of the Secretary of the Navy, Washington, D. C., on Oct. 6, 1915. The Board organized by electing Thomas A. Edison, Chairman, Peter Cooper Hewitt, First Vice-Chairman, William L. Saunders, Second Vice-Chairman, and Thomas. Robins, Secretary. All of these officers are members of the American Institute of Mining Engineers. The other members of the Board are given below, and those who are members of the Institute are marked with an asterisk: *W. R. WHITNEY MATTHEW B. SELLERS. L. H. BAEKELAND. HUDSON MAXIM. FRANK JULIAN SPRAGUE. HOWARD T. COFFIN. BENJAMIN C. LAMME. ANDREW J. RIKER. R. S. WOODWARD. HENRY A. WISE WOOD ARTHUR GORDON WEBSTER. ELMER A. SPERRY. A. M. HUNT. *BENJAMIN B. THAYER. ALFRED CRAVEN. *J. W. RICHARDS. *SPENCER MILLER. *LAWRENCE ADDICKS. WILLIAM LE Roy EMMETT.

Jan 12, 1915

By Kendall F. Born

Production of crude oil in Tennessee during 1939 was slightly more than 51,000 bbl., an increase of about 10,000 bbl. over 1938. The product,ion by counties and by fields is shown in Table 1. The increased production has rcsulted from continued activity in the Upper Cumberland district, especially in Clay County, where approximately 37,000 bbl. were marketed off the lease. This figure includes a single well in the old Tinsleys Bottom pool on the Clay-Jackson County line, although the well is in Jackson County. The "Mississippi lime" produced 10,811 bbl. in Scott and Morgan Counties, a decrease of 2568 bbl. from the 1938 production. Production during the year from some half-dozen scattered wells in eastern Clay, Pickctt, and Fentress Counties, on which there are no accurate figures, is estimated at 1000 barrels.

Jan 1, 1940

By Kendall F. Born

Production of crude oil in Tennessee during 1939 was slightly more than 51,000 bbl., an increase of about 10,000 bbl. over 1938. The product,ion by counties and by fields is shown in Table 1. The increased production has rcsulted from continued activity in the Upper Cumberland district, especially in Clay County, where approximately 37,000 bbl. were marketed off the lease. This figure includes a single well in the old Tinsleys Bottom pool on the Clay-Jackson County line, although the well is in Jackson County. The "Mississippi lime" produced 10,811 bbl. in Scott and Morgan Counties, a decrease of 2568 bbl. from the 1938 production. Production during the year from some half-dozen scattered wells in eastern Clay, Pickctt, and Fentress Counties, on which there are no accurate figures, is estimated at 1000 barrels.

Jan 1, 1940

By C. W. Sherman, J. Chipman, H. I. Elvander

J. F. Elliott—This is an excellent piece of work and makes a chemical metallurgist more enthusiastic than ever about what can be done with multicomponent systems, if we have satisfactory data. I have a remark to make on the interpretation of fig. 5. First, I will comment on the problem of activities in solutions. The iron-sulphur system has in its phase diagram an intermediate solid phase FeS. The occurrence of an intermediate phase is normally associated with negative departures from Raoult's law over a portion of the activity curves in the liquid. (Perhaps it would be better to reserve the phrase "departure from ideality" to departures from Raoult's law line rather than to departures from Henry's law line). Fig. 5 indicates that the deviation of the sulphur activity curve from the Henry's law line is negative;

Jan 1, 1951

By Arthur Taggart

THE following conclusions on the work of the Hardinge mill are based on data furnished to the writer by the Hardinge Conical Mill Co. in the form of the mesh cards hereto appended. Energy units (E. U.) and relative mechanical efficiencies (R. M. E.) are computed by the "volume method" of Stadler.1 Screen apertures used are the average apertures of testing screens of the meshes given. Card 122. June 28, 1912. Vipond Porcupine Mines Co., Ltd., Schumacher, Ont., Canada. Ore from mill bin. Gangue, quartz and basalt. 4.5 ft. by 13 in. ball mill. Capacity, 48 tons per 24 hr. Charge, 4,000 lb. balls. Speed, 33 rev. per minute. Horsepower, 15 to 17. Water, 100 per cent. by weight. (50 per cent. ?) Product deslimed and oversize reground-in pebble mill, see Card 113. Feed to mill through 2-in. mesh.

Jan 7, 1915

By Chester O. Ensign

Results of the application of geologic knowledge to grade control have been remarkable. Grade reduction from dilution has been diminished from greater than 9% at the time of the program's beginning to about 2% at present. This has resulted in an increase of about 1.8 lb of copper per ton of ore mined and has made a substantial contribution to earnings at White Pine during the past two years. Even more improvement is expected in the future. The White Pine orebody, situated in the southwestern portion of the Keweenaw peninsula of upper Michigan, is a gently dipping stratiform or bedded deposit. Copper distribution is stratigraphically controlled with higher values being confined to specific beds in the ore column. Room-and-pillar mining is practiced. Mining technique and geologic characteristics present a special array of problems in controlling the grade of ore.

Jan 4, 1964

By Mahesh C. Jha

Arsenical gold ores occur in many parts of the world, including numerous mines in Canada and the western United States. Free gold is often finely disseminated in the grains of sulfide minerals, arsenopyrite, pyrite, orpiment and realgar. Generally a sulfide concentrate is produced by flotation. Arsenical ores or concentrates are not amenable to direct cyanidation and therefore are considered refractory. A wide variety of roasting equipment and conditions have been used by the mills to remove arsenic and sulfur from these concentrates. The resulting calcine is easy to cyanide and gold is recovered from the cyanide solution by zinc dust cementation. Room-temperature potential-pH diagrams and high-temperature phasestability diagrams are presented to discuss the chemistry of the gold cyanidation, cementation, and roasting steps in the presence of arsenic. The environmental aspects of arsenic discharge are also included.

Jan 1, 1984

By William L. Fink, Dana W. Smith

In parts I1 and II2 of this series, there were presented results of investigations on the age-hardening of an aluminum-copper and an aluminum-magnesium alloy. It was shown that the simple precipitation theory of hardening3 adequately explained the aging phenomena, including certain so-called "anomalous" behaviors which had caused other investigators to reject or modify the precipitation theory. However, these papers did not discuss the double aging peaks, which have been stressed in recent articles by Dr. M. Cohen4 and Dr. M. L. V. Gayler.6 The present paper is devoted to an explanation of this "anomaly." Fig. 1 is a generalized schematic representation of aging curves at different temperatures. Curve A corresponds to the aging at the lowest temperature, and D at the highest temperature. Certain previous investigators have explained curve A and the initial peaks

Jan 1, 1938

By William L. Fink, Dana W. Smith

In parts I1 and II2 of this series, there were presented results of investigations on the age-hardening of an aluminum-copper and an aluminum-magnesium alloy. It was shown that the simple precipitation theory of hardening3 adequately explained the aging phenomena, including certain so-called "anomalous" behaviors which had caused other investigators to reject or modify the precipitation theory. However, these papers did not discuss the double aging peaks, which have been stressed in recent articles by Dr. M. Cohen4 and Dr. M. L. V. Gayler.6 The present paper is devoted to an explanation of this "anomaly." Fig. 1 is a generalized schematic representation of aging curves at different temperatures. Curve A corresponds to the aging at the lowest temperature, and D at the highest temperature. Certain previous investigators have explained curve A and the initial peaks

Jan 1, 1938

By Bradley Stoughton

THE importance of magnesium alloys as engineering materials has increased rapidly in the past few years. The most important properties of magnesium alloys are their lightness and strength, which result in their. extensive use in aircraft and automobile construction. Recent progress in the metallurgy of magnesium seems to offer hope of the production of the pure metal at a reasonable cost. The use of magnesium would doubtless increase greatly if it could be produced at a cost comparable with that of aluminum. AA preliminary survey of the magnesium-base alloys shows that the most promising from a practical standpoint are magnesium-aluminum and magnesium-zinc as binary alloys, and magnesium-zinc-aluminum as ternary alloys. The research reported in this paper is a preliminary study' of binary magnesium-aluminum and magnesium-zinc alloys, as an introduction to a series of further investigations.

Jan 2, 1926

By William G. Kegel

Problems involved in putting the gob back underground in modern deep mines we dealt with. In particular, the problems associated with haulage of the gob back to the mine, the blown gob method of dispersion underground, and handling the refuse as slurry are discussed. Some alternative methods of disposal are presented.

Jan 1, 1976

By Rollin Farmin

"SWELLING GROUND" delivers pressure on mine timbers that originates in expansion of the wall rock, whereas "heavy ground" delivers only gravitative pressure. Of the several possible causes considered, the swelling is attributed to the physical surface action of water on gouge and flaky rocks at the periphery of the mine opening.

Jan 1, 1944

By F. W. Denton

Much has been written about the possibilities of the Vermilion and Mesabi ranges of northern Minnesota as producers of large quantities of high-grade iron-ore. The Mesabi range in particular has attracted considerable attention on account of the proximity of the ore-deposits to the surface, which has been as-

Jan 1, 1898

Only the coal of the Sunnyside district in Carbon county is coked. Two companies, the Utah Fuel Company and the Columbia Steel Corporation, operating adjoining mines at Sunnyside and Columbia, produce coke. The Utah Fuel Company has 81 9 beehive coke ovens at Sunnyside. Only 350 ovens are being operated at the present time, largely because the smelters which had been using Sunnyside coke changed their equipment from blast furnaces to reverberatory furnaces

Jan 1, 1925

By William E. Ford, Edward Salisbury Dana

I. Sul~harsenites, Sulphantimonites, etc. In these sulpho-salts, as further explained on p. 320, sulphur takes the place of the oxygen in the commoner and better understood oxygen acids (as carbonic acid, H2COs, sulphuric acid, H4S04, phosphoric acid, H3P04, etc.). The species included are salts of the sulpho-acids of trivalent arsenic, antimony and bismuth. The most important acids are the ortho-acids,

Jan 1, 1922

By Karl Eilers

During my stay of two years in this country, I have heard of only four electric mine-locomotive plants, of which three were built by the firm of Siemens & Halske, and the fourth by the Allgemeine Elektricitatsgesellschaft, both of Berlin. The earliest of these was established in 1882 in the royal coalmines at Zaukeroda, Saxony. In 1883, the Consolidated Paulus and Hohenzollern colliery at Beuthen put in a plant; and in the

Jan 1, 1892