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By L. W. Bahney

Many methods for the determination of gold or silver, or both, in cyanide solutions have been published, which with care in manipulation, and modification in some cases, will give results that are satisfactory. It is possible to classify or group these methods as follows: 1. Evaporating the solution in a porcelain or agate-ware dish containing litharge,l or in a "boat" made of lead foil. 2. Forming a lead sponge containing the precious metals by means of zinc shavings,2 zinc dust,3 or a piece of aluminum.4 3. Decomposing the cyanide solution with an acid and precipitating the precious metals by the use of one or a combination of some of the following: Copper sulphate,5 sodium sulphite,6 hydrogen sulphide,' cement copper.ll 4. Precipitating the silver by zinc dust held in a Gooch crucible and determination with a standard solution of sulphocyanate.9 5. Electrolysis.l0 . 6. Colorimetry.ll

Jan 1, 1915

By George Ashley

IT has been said that the Pittsburgh bed is the most valuable single mineral deposit yet known to man. The figures in Table 1 are presented in substantiation of that claim. TABLE 1.-Pittsburgh Coal Bed to Dec. 31, 1934 Estimated Recov- State Thousands of ( Value erable Reserves Tons Mined (1935), Thousands of Tons Pennsylvania 3,144,000 $4,922,000 7,500,000 Ohio 493,391 843,699 3,000,000 West Virginia 650,000 1,027,000 5,500,000 Maryland 183,224 254,681 20,000 Totals 4,470,615 $7,047,380 16,020,000 PRODUCTION AND VALUE In order that the figures of Table 1 may have any weight, a statement must be made to show how they were arrived at. Because, to the writer's knowledge, no accurate separate figures ever have been kept of the production and value of the Pittsburgh coal bed, the states will be considered separately.

Jan 1, 1936

By R. Taggart, G. R. Purdy

DURING a study of the tempering of ß-quenched alloys of cobalt in titanium, parallel lines were observed crossing certain faces of retained-ß crystals in the early stages of tempering, Fig. 1. The lines closely resemble stress-induced martensite' or substructures attributed to clusters of faults in titanium-nickel2 and copper-silicon3 alloys. The markings were observed only in intensely etched quenched and tempered alloys having compositions ranging from 4.5 pct* Co (the composi- formed by the lines was reproduced upon repolishing and reetching. Close metallographic examination indicated that the markings were troughs, Fig. 2, and that the characteristic surface substructure persisted within the troughs. The occurrence of the troughs was associated with the age hardening reaction due to the metastable u) phase (previously reported in titanium-cobalt alloys by Raub and Beeskow4 and indicated in this work by the broadening of 0 diffraction peaks and by hardnesses approaching 600 Dph). The troughs

Jan 1, 1961

By J. S. Browning

The pegmatites of the Kings Mountain-Lincolnton, N. C., area constitute the largest known domestic reserve of beryl and spodumene. The reserve is estimated to contain 90 million tons of pegmatic material with 1,280,000 tons of recoverable Li2O (lithia) as spodumene.1 The pegmatites also contain 0.4 to 0.5 pct beryl disseminated throughout the orebodies. The pegmatites may contain a potential reserve of 240,000 tons beryl, equivalent to approximately 34,000 tons of BeO. Different flotation methods for separating beryl from feldspar or quartz, or both, have been developed by various investigators.2,3,4,5,6,7 On the other hand, published information is limited on concentration of spodumene-beryl ores. As the response of beryl and spodumene to flotation is essentially the same, a successful separation of the two minerals depends upon use of a selective depressant or a selective collector for one of the minerals.

Jan 7, 1961

By Newell G. Alford

The data in this paper were collected to show both the volume and speed with which bituminous mines have indefinitely suspended operation while economic advantage in the industry has so gravely declined. The study was limited to the bituminous coal-mining states east of the Mississippi River, wherein conditions affecting production and demand are more common respectively to all of the mining districts included and represent about 95 per cent of the nation's coal mining. Data for the compilation of these statistics and for the construction of these graphs have been obtained in all cases from state mine department reports, except from those of Ohio and Virginia. In Virginia essential individual mine data were secured from an authentic source, but no individual Ohio mine information is obtainable, because all Ohio fact-gathering agencies are prohibited by law from revealing such data. In other states the facts were tabulated and later checked with the cooperation of Chief Mine Inspectors. In all, excluding Ohio, over 17,000 individual annual mine returns were examined. Special information was secured from each state mine department about suspensions in 1932. Accurate information was not available from all states about nine abandonment due to exhaustion of coal reserves, and while these were completed for several states, it has not been shown because it was not perfected for all states. However, the total observed sample mas comprehensive enough to show that exhaustion accounts for a very limited part of the suspended production. Wherever mention is made of '(suspended productionJ' the largest annual output of the mine in the five years prior to suspension has been taken as the measure of its probable production had it continued to operate. A mine is not regarded in this category, as having suspended, when it merely ceases to produce. The word "suspension" is used only where there is a complete abandonment of activity for an indefinite period, as evidenced by the fact that both ventilation and pumping are discontinued.

Jan 1, 1934

By Charles R. Keyes

During the past decade the genesis of the lead- and zincdeposits of the Mississippi valley has received special attention from many distinguished observers. But their united egorts, instead of settling all disputed questions, have, in many respects, involl-ed the general problem in greater uncertainty than would be thought possible under the circumstances. In place of the harmony of opinion that might be expected, there is unexpected disagreement, largely due to the fact that, instead of giving attention to a possible multiplicity of ore-producing conditions among the different deposits, the attempt has been made to bring all deposits under a single genetic head. To a new observer of the lead- and zinc-deposits of the Mississippi valley, it appears at the outset that all the deposits cannot possibly have had the same genesis. In fact, different modes of origin have been often asserted for the ore-bodies, but the difficulty has been that each writer has referred them either all to one category or all to another, and no intermediate ground has been considered possible. Such a position now appears to be clearly untenable. The opinion that, in the deposits of the region under consideration, the ore-materials represent original depositions, made at the time the rocks themselves were formed, is no longer held by any authority, and therefore need not be considered here. Of late years, a number of writers have attempted to account for the presence of the lead- and zinc-ores on the hypothesis that the metallic materials arose in heated solutions from the

Jan 1, 1902

One of the most unusual assignments in the his¬tory of Loffland Bros. Co. is now in progress with the drilling of a 72-in. diam. shaft in Nevada for the United States Atomic Energy Commission. Projected depth being 3200 ft, by volume, this is the same as a 216,672-ft hole 83/4 in. in diam. Every aspect of the operation is king-sized. The 15,000-lb bit moves into position over the well on a specially-made railroad car riding on rails 14 ft apart. The single drill collar weighs 300,000 lb, is 60 in. in diam., and 43 ft long. The drill pipe is 133/s-in. 72-in. N-80 casing fabricated with special tool joints. The bit chews up 1.05 cu yd of rock for every ft of penetration (This is equal to the volume of 67.71 ft of 83/4-in. hole.

Jan 9, 1964

By Bailey, Lewis Newton

Bailey, Lewis Newton, Master Engineer, Senior Oracle, 4th Regiment, U. S. Engineers, Headquarters Company, died of pneumonia, at Camp Merritt, N. J., on April 30, 1918. Baird, Louis, Lieut., Royal Field Artillery, British Army, died on the battlefield in 1915. Ballamy, John H., Capt., 103d Engineers, killed in action near Fismes, Aug. 9, 1918. Burt, Andrew, died in active service, 1916. Cobeldick, William Morley, Royal Engineers, died from gas poisoning on October 7, 1915. Dougall, Ralph, 4th University Co., Princess Patricia Regiment, killed in action early in the war. Evans, Alfred Winter, Lieut.-Col., New Zealand Rifle Brigade, D. S. 0., D. C. M. killed in action on October 12, 1917. Gorman, Thomas C., Lieut., Canadian Engineers, killed in France, Mar. 18, 1918. Hague, William, 1st Lieut., Engineer Officers' Reserve Corps, died in active service, Jan. 1,, 1918. Hall, William T., Capt., Royal Flying Corps, killed in action, May 19, 1917.

Jan 11, 1918

By W. A. Tiller, J. P. McHugh

THE phase diagram of the Ge-Te system was first investigated by Klemm and Frischmuth.' They arrived at the phase diagram shown in Fig. 1 indicating the presence of a peritectic phase boundary at the 50 at. pct Ge composition. Later, Schubert and Fricke2 obtained data which suggested to them the possible existence of a eutectic at about 55 at. pct Ge. In order to resolve these differences, we have carefully studied this system in the region 40 to 60 at. pct Ge using both the conventional thermal analysis technique and a new solidification technique.3y4 The alloys were prepared from semiconductor grade germanium and 99.999+ Te by reacting the elements in evacuated, graphite coated, vycor tubes. The samples were placed in a thermal analysis apparatus described elsewhere4 and cooling curves were taken of each alloy to determine the liquidus surface. The cooling curve for a 50 at. pct alloy shows two distinct arrests about 1°C apart which

Jan 1, 1961

By Newell Alford

THE data in this paper were collected to show both the volume and speed with which bituminous mines have indefinitely suspended operation while economic advantage in the industry has so gravely declined. The study was limited to the bituminous coal-mining states east of the Mississippi River, wherein conditions affecting production and demand are more common respectively to all of the mining districts included and represent about 95 per cent of the nation's coal mining. Data for the compilation of these statistics and for the construction of these graphs have been obtained in all cases from state mine depart-ment reports, except from those of Ohio and Virginia. In Virginia essential individual mine data were secured from an authentic source, but no individual Ohio mine information is obtainable, because all Ohio fact-gathering agencies are prohibited by law from revealing such data. In other states the facts were tabulated and later checked with the cooperation of Chief Mine Inspectors. In all, excluding Ohio, over 17,000 individual annual mine returns were examined. Special infor-mation was secured from each state mine department about suspensions in 1932. Accurate information was not available from all states about mine abandonment due to exhaustion of coal reserves, and while these were completed for several states, it has not been shown because it was not perfected for all states. However, the total observed sample was comprehensive enough to show that exhaustion accounts for a very limited part of the suspended production. Wherever mention is made of "suspended production" the largest annual output of the mine in the five years prior to suspension has been taken as the measure of its probable production had it continued to operate. A mine is not regarded in this category, as having suspended, when it merely ceases to produce. The word "suspension" is used only where there is a complete abandonment of activity for an indefinite period, as evidenced by the fact that both ventilation and pumping are discontinued.

Jan 1, 1933

By William E. Ford, Edward Salisbury Dana

1. Normal Class (31) Axinite Type 2. Asymmetric Class (32) Calcium Thiosulphate Type Mathematical Relations of the Triclinic System 216. Crystallographic Axes. - The triclinic system includes all the forms which are referred to three unequal axes. with all their intersections oblique. When orientated in the customary manner one axis has a vertical posi-

Jan 1, 1922

By James Howe

EVERY engineer and user of wire rope is desirous of information that will enable him to determine whether the performance of any particular piece of rope is satisfactory, and what conditions can be changed so as to increase the life of a rope. In most cases, it is far from easy to analyze the conditions of service and tell which is the greatest factor in determining the life of wire rope. If we start on a layout for an entirely new rope system, the task of making conditions satisfactory is simplified so far as the engineering details are concerned; but if the plant requiring wire rope is in operation, any change is likely to involve the expenditure of consider-, able money to replace and change over machinery that must be kept in constant operation, because a large monetary loss will result from a shutdown for even a few days. Often wire rope is kept operating under bad conditions, as the user thinks that it is cheaper and quicker to replace the rope than to make alterations in the hoisting machinery. A typical case is a metal mine operating in what is now almost the center of a large mining city, where it owns a few acres of mineral rights. It was expected that the shaft would go to a depth of 1000 ft. (305 m.), so a moderate sized rope, about 1 ¼ in. (31.7 mm.), was used on a 6-ft. drum with a 7-ft. head-frame sheave and rather short lead from drum to head sheave. This mine has gone deeper each year until, it is now 2500 ft. deep and the rope speed has been increased from 1500 ft. per min. to over 3000 ft. The original rope just filled the drum in one layer, now it overwinds three layers. The original ropes were probably 6 X 19 crucible steel and lasted from 12 to 18 mo.; now, the highest grade plow steel is used, yet the average service is only about 6 mo. The cause is not hard to find. If the engineers had known at the outset what would be done with this hoist, the design would have been very different. Conditions at this mine, from a wire rope standpoint, have gradually become worse and it is difficult to see how rope service on this hoist can be com-pared with the service of previous years with any fairness to the wire-

Jan 2, 1922

By E. J. KENNEDY

THE 142D MEETING of the Institute is rapidly shaping up with splendid prospects of a strong technical program and the lighter side of this annual occasion amply provided for. The date is February 20 to 23. The technical sessions will be held in the Engineering Societies building; the smoker-dinner, the informal dance, and the annual reception and dinner, at the Commodore Hotel, Monday, Tuesday and Wednesday respectively. The news to date on the technical side is as follows: Mining Methods-Subsidence The Mining Methods Committee has prepared an interesting program which will be divided into two sessions to be held early in the week. At the first there will be papers on mining methods and development, including a description of the "Sinking and Equipment of No. 2 Shaft at Minas de Matahambre," by Dudley D. Homer and R. H. Cromwell. They describe in considerable detail the equipment used and the practice followed in sinking this important shaft, giving detailed costs and performance figures. Hoist¬ing ?arrangements and mining practice at the "Red Ore Mines of the Woodward Iron Co. at Bessemer, Ala.," are described by Tenny C. DeSollar, superintendent of mines, in a second paper. At this session of the Mining Methods Committee, H. M. Roche and R. E. Crockett, of the Committee on Eastern Magnetite Mining and Milling Methods, will present their paper, "Iron Ore Mining at the Scrub Oak Mine." This mine is in the highlands of New Jersey about 40 miles west of New York City. Prof. Robert K. Warner of Yale University will present a paper on "The Selection of a Mining System," which should have an interesting discussion. Pierre R. Hines, of Portland, Ore., will present, with stereopticon slides, his paper on "The Owyhee Tunnels, U. S. Reclamation Project, Owyhee, Oregon," describing one of the recent irrigation undertakings.

Jan 1, 1933

By Robert Williams

A description is given of a double heat treatment of 60-40 brass. Photomicrographs are included to show the changes that take place in the microstructure on reheating the water-quenched specimens. A wide variation in the mechanical properties may be obtained by the described heat-treatment method. ON SEVERAL occasions, when 60-40 brass is first obtained in the beta condition by quenching at about 825° C. and is then reheated, the writers have noticed that recrystallization will take place in the form of twin crystals at the grain boundaries of the original beta crystals. It was, therefore, thought that interesting results would be obtained if this twinning process was studied further, especially as to the temperature at which it first occurs. The material used in the investigation was a bar of extruded muntz metal, 1/2 in. in diameter, and of the following composition: Copper, 60.21 per cent.; zinc, 39.73 per cent.; lead, trace; iron, trace; tin, nil. Specimens I in. in length were sawed from this bar and a hole was drilled into the side of each specimen until it reached the center, and the tip of a platinum-platinum rhodium thermocouple was inserted. A small Hoskins' resistance-type electric furnace was used for heating the specimens. The specimens were first heated at 840°C. for 2 hr. and then quenched in cold water, in order to get the material entirely in the beta state. In every case, in the reheating process, the furnace was brought to the desired temperature before the specimen was introduced. The time occupied in preheating was from 20 to 30 min. By sawing back 1/4 in. on each side of the hole, two parts were obtained from each specimen

Jan 3, 1924

By L. D. Jaffe

THE data recently published1-" on heat treatment of titanium alloys have not been readily systematized into an overall picture. When the ß titanium phase transforms isothermally at low temperatures, the hardness follows a typical age-hardening pattern, going through a peak as schematized by the "hardness" vs "time of isothermal transformation" coordinates of Fig. 1. As the temperature is raised, the peak will decrease in height and occur at shorter times; slowing must however take place as the /3 transus is approached. The brittle microconstituent in the region of peak hardness has been termed /3'. Its structure is still undetermined but it is clearly a transition stage from soft /3 to the £ + a that is found at the right of the peak. On continuous cooling, high cooling rates correspond to short times on Fig. 1; abscissa labeling has been added accordingly. Extremely rapid cooling will retain soft /3; very slow cooling will precipitate soft a; intermediate rates give hard 8'. Increasing distance from the water-quenched end of a Jominy hardenability bar corresponds to slower cooling (right on Fig. I), but the range of cooling rates covered by a Jominy bar is only a small portion of that shown in the figure. The p-stabilizing alloying elements retard the transformation process, moving the material to the left on Fig. 1. A lean alloy is harder water-quenched (P') than air-cooled (/3 +a); a rich alloy is harder air-cooled (/3') than water-quenched (/3). Examples of the position of various compositions with respect to the curve, based on limited data in the literature, are given at the top of the figure. Oxygen and carbon accelerate the transformation process, moving the material to the right on Fig. 1. If an alloy quenched quickly enough to retain soft /3 is reheated below the £ transus (tempered), it ages, going through a hardness maximum as time increases (moving right on Fig. 1). Material which after cooling from the /3 range lies on or right of the hardness peak, will move still further right on tempering, and so soften. Since the rate of the tempering (aging) reaction increases with temperature, the figure also may be used to represent the variation in properties with tempering temperature, at short tempering times. The simple picture given here neglects martensite transformation, as well as differences between decomposition products of /3 formed by direct isothermal transformation and those formed by quenching and tempering. It may nevertheless be of use as a guide for practical heat treatment and for further research.

Jan 1, 1955

By Homer Griffield Turner

The nature and comparative features of anthracite and bituminous coals have been discussed by the writer in two previous papers.' Although this paper is offered as a further contribution to the subject, it seems desirable at the outset to repeat some of the descriptive matter of the early works in order to show the actual connection between various constituents of both coals and the new photomicrographs and other physical and chemical properties. Structure of Anthracite and Bituminous Coals A lump of bituminous coal (Fig. 1) is readily seen to be composed of layers differing from one another in texture, luster and thickness. There are, in general, three kinds of layers, although only two are usually seen. One is deep black, very compact, and has a bright luster; another is grayish black, has a duller luster and is less compact; the third is black, dull and porous in appearance, but because of its thinness is not often seen except on parting surfaces. This last material is charcoal. American students of coal morphology use the names anthraxylon, attritus, and fusain to designate these three constituents of laminated coal. Anthraxylon refers to the brightest bands, attritus to the duller layers, and fusain to the charcoal. Close examination of a lump of bituminous coal shows the brightest deep black layers to be embedded in the duller grayish black laminae. These deep black layers are lens-shaped and vary in thickness from thin sheets to over half an inch. They are often so continuous through the lump that their tapering terminae are not noticeable. On careful examination the duller grayish black laminae (Fig. 7) are seen to contain many very thin sheets of this very bright black material. The charcoal

Jan 1, 1930

By E. C. Pechin

Secretary's Note.—Mr. Bramwell was born in 1846, at Liverpool, England, his father being English, and his mother American, of Scotch ancestry. Brought to the United States in early childhood, he was educated at the public schools and graduated from the College of the City of New York. He subsequently studied his profession as a mining engineer at the Royal School of Mines, Berlin, Prussia, and was for a short time in the service of the Prussian government at Konigs hutte. Returning to this country in 1871, he was employed during succeeding years as mining engineer, chemist, and manager at various fnrnaces and iron works in Pennsylvania and the Southern States until, in 1883, he became actively engaged in the development of the Flat-Top coal-field of southwestern Virginia, in which region the town of Bramwell was named after him, in recognition of his services as a pioneer of the great industry which he did so much to promote. After prolonged and fluctuating ill-health, he died, July 13, 1894, at Paris, France. At the opening session of the Bridgeport meeting, the Secretary announced his death, and Mr. Pechin, being called upon, made the remarks reported below.— R. W. R. Widely as Joseph Herbert Bramwell was known, I. think I knew him somewhat better than any one else. After finishing his studies abroad, he came to this country, a very young man, seeking an engagement. This was about the beginning of 1871, as I remem ber, and I was then trying to make iron at Dunbar, at the foot of the Allegheny mountains, in Fayette county, Pa. His engaging manner and charming personnel, combined with his letters of intro duction, made me more than satisfied in securing his services as my chemist. At the outset we lived a sort of pioneer life, and for many months he was practically a member of my family, and the affection then formed remained unbroken to his dying day. I vividly recall the circular of April, 1871, signed by Eckley B. Coxe, R. P. Rothwell and Martin Coryell suggesting a meeting at Wilkes-Barre, Pa., for the purpose of forming the American Institute of Mining Engineers. At the last moment, prevented from going, I sent Bramwell; and I am more than glad that his name appears among those whose sagacity established an Institute that has become illustrious by reason of its numbers, the character of its members, its invaluable papers and its enormous influence for good

Jan 1, 1895

By Robert Glass Cleland

[DATA OF THE YEAR 1950 COMPARED TO 1909 (FIRST CONSOLIDATED REPORT) CONSOLIDATED NET INCOME Without deduction for depletion of mines $ 42,395,465 $7,337,252 After deduction for depletion of mines $ 4,112,604 $7,337,252]

Jan 1, 1952

By Charles Behre

THIS paper deals with recent geologic studies in the slate belt of Northampton, Lehigh and Berks counties, Pennsylvania. The work was conducted under the auspices of the Pennsylvania Topographic and Geologic Survey. Three years have now been spent in detailed consideration of the economic geology of this region. In the field, particular attention was paid to the bearing of geology on quarry development and property valuation and the object of this paper is to summarize the results from that viewpoint. Excellent studies of a somewhat similar nature have already been carried out by Bowles,1 but with the emphasis upon the details of quarrying and fabricating methods, rather than upon the geologic relations. THE NORTHAMPTON-LEHIGH-BERKS DISTRICT Location The region here discussed lies in east-central Pennsylvania and extends southwestward from Delaware River, on the New Jersey line, to the Schuylkill in north-central Berks County. It is an elongated belt occupying the northern sections of the three counties mentioned and lying along the southern edge of Blue Mountain. Its length is about 50 miles and its average width five or six, though in places it attains a maximum of 10 miles.

Jan 1, 1928

By J. Hunter

LouisiaNa ranks fifth among the oil-producing states. In 1941 the state-wide production was slightly in excess of 118,000,000 bbl. of crude oil and conden-sate—an increase of 15,000,000 bbl. over the total production for the year 1940. During 1941, south Louisiana produced approximately 90,900,000 bbl. of oil, while north Louisiana produced approximately 27,000,000. South Louisiana, therefore, produced about 3¼ times more oil than north Louisiana. During the past year, 574,800,000 M cu. ft. of natural and casinghead gas were produced in Louisiana; thus 1941 gas production exceeded the 1940 production by 104,900,000 M cu. feet. Completion records for the year 1941 show that 1512 wells were completed in or adjoining producing fields. These wells, which were drilled to extend known producing areas or were located within producing areas, are not considered as wildcat wells. Of the total number of field wells drilled, 1152 wells found production; the remaining 360 were junked or dry and abandoned. This means that 76 per cent of the wells drilled were successful. Considering the precarious nature of oil-field development, this percentage of new producing wells is exceedingly satisfactory. Of the total number of field welis com-pleted as producers, approximately 86 wells found new and distinct producing sands. During the past year, 30 new fields were found. Four parishes—namely, Caldwell, Catahoula, Orleans, and Natchitoches— entered the ranks of oil-and-gas-producing parishes in the state during that period. This brings the total number of oil-and-gas-producing parishes in the state up to 48. Thus, 75 per cent of the parishes in Louisiana now contain one or more oil and/or gas fields. Although sufficient data are not available to list the addition reserves found in Louisiana during 1941, it is felt that such reserves undoubtedly exceed twice the total production for that year, or at least 200 million barrels. In reserves, therefore, Louisiana ranks third among the various oil-producing states. South Louisiana Although 16 new fields were found in south Louisiana, the outstanding developments in that part of the state were not limited to new discoveries. In fact, most of the increase in reserve in that area has been most consistently accumulated through extensions of known producing sands and through the finding of new sands in already productive fields, especially at depths below the presently producing sands. Since data concerning most of the new extensions and sands are too extensive for discussion here, the more important developments arc briefly outlined below: Abbeville, Vermilion Parish.—Production extended ½ mile to the west. Anse La Butte, St. Martin Parish.—New oil sand discovered at 9400 ft., thus extending production to east flank. West flank defined by dry holes. Barataria, Jefferson Parish.—New oil sand discovered on east side of field at 7620 ft. New

Jan 1, 1942