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The library of the above-named Societies is open from 9 A. M. to 10 P. M. except on holidays. It contains about 70,000 volumes and 90,000 pamphlets, including sets of technical periodicals and publications of scientific and technical societies. Members of the Institute, with few exceptions, are forced to spend a portion of their time in localities isolated from sources of information. To these the Library, through its Library Service Bureau, can render valuable service through correspondence; letters requesting information will receive especial attention. The Library is prepared, to furnish references and photographic copies of articles on mining and metallurgical subjects; to determine the existence of mining maps, and to furnish general information on the geology and mineral resources of all countries. All communications should be made as definite as possible so that the information received may be what is desired and not include collateral matter which may not be of interest. The time spent in searching for such collateral matter will be saved, and the information will be sent more promptly and in more usable shape. HARRISON W. CRAVER, Director.

Jan 5, 1919

By J. L. Gillson

In this past year of our Institute's life, February 1960 to February 1961, we had some major problems to face, as did our members, since businesses in which they were engaged were feeling the recession. The major problems confronting us during this past year were: 1) Financing the new Engineering Center. 2) Keeping our three almost autonomous societies working together and toward a stronger AIME. 3) Cooperation with other engineering societies the Functional Plan. 4) Licensing and registration, and the Model Law. 5) The reorganization of the Council of Section Delegates. 6) Combatting the slump in the appeal of engineering to the young students.

Jan 4, 1961

HAVING previously shown you how ores are found and mined, and also how they are prepared and disposed for smelting, and then how the blast furnaces and other furnaces are made for purging their earthiness, all this would be as nothing if I did not proceed to show you the method of smelting them. Therefore, in the present chapter I wish to show you how you must proceed in this very important operation, telling you all I have seen and also how much work with this kind of blast furnace I have done or directed. For this reason I tell you first to take by weight or measure the quantity of ore that you wish to smelt and, particularly if it is a kind that contains silver, break it into small pieces about the size of [52v] beans. If the ore had previously needed evaporation by fire or cleaning by washing, you will have had this done well and have had it properly prepared by a master sorter or others. A layer of this is arranged on a bed of planks, bricks, or flat stones in front of the blast furnace and its companion is placed on top, then a quarter part of galena or a third if you can obtain it. Then an equal part of crushed iron slag or slag from the same or different ore is added. These materials are spread in layers one above the other. When the blast furnace has been constructed as taught above, correct in all its parts, and is full of well-kindled burning charcoal, then fill it up with charcoal and admit water to the bellows machine. When you see that it is well kindled again from this wind and that the flames begin to come out forcefully on top, work it down with a little rake and fill it up again. Then the pannier is filled with new charcoal, the blast furnace heaped full, and another basketful of the said composition of ore is also put on top. Proceed in this way, continually adding charcoal and ore as long as you have any, or as long as you wish to keep up the work, maintaining the blast furnace always full, or continuing in this way until the bottom of the blast furnace is filled with melted materials. Decide this by judgment, or by seeing through the mouth of the tuyère where the wind of the bellows enters that they are level with this. Then with an iron tool open the hole that was left as an outlet in front of the blast furnace and allow all the metal with its slag to run out. These two things, flowing through the chan-

Jan 1, 1942

By R. V. Norris

The anthracite coal trade, with a shipment averaging about 70,000,000 tons per year, differs essentially from other coal business, iii the fact that the larger sizes, comprising about 65 per cent. of the total, are used almost exclusively for domestic purposes, principally during the winter months; and that for proper combustion close-sizing is imperative, so that eight sizes are made; broken, egg, stove, and nut, known as prepared sizes, and pea, buckwheat, rice, and barley, known as steam sizes. These sizes are made in the regular course of preparation, and but little variation in the natural percentage of each is practicable. Thus it is necessary either to work the collieries intermittently, or to dispose of all the varying sizes in their fixed proportions. Unfortunately, the market does not at all times absorb the coal in proper proportions, and rather than interfere with the regular operation of the mines it has been found economical to provide storage for the excess. While the cellars of' the consumers are the great storage-plants of the country, this capacity is not under the control of the trade, except so far as reduced prices during the spring and summer months may tempt the use of this reserve. The same remark applies but with less force to the retail yards, which, though usually small, store in the aggregate a large amount of anthracite. While every effort is made to utilize to the utmost the individual storage-capacity of the country, there still remains the necessity for taking care of the irregularities of the market by the construction of storage-plants under the direct control of the producers. Such plants are usually the property of the railroads, and are situated at points most convenient from a traffic stand-point.

Jan 1, 1912

By P. Davey Wheeler

San Francisco meeting, September, 1915) IN an article in the General Electric Review, January, 1915, reference was made to the X-ray examination of a steel casting 9/16 in. thick. Fig. 1 shows one of the radiographs thus obtained. All these radiographs showed plainly the tool marks on the surface of the casting. All but one showed peculiar markings the shape of which strongly suggested that they were indeed the pictures of holes in the interior. A circular piece, 1 in. in diameter, was punched from the casting at a point where the radiograph shown in Fig. 1 indicated that a blow-hole should be found. (Location of sample shown by circle in Fig. 1.) Fig. 2 is a photograph of the end of the punching, showing the .hole that was found. Since that article was written it has seemed desirable: (1) to obtain data from which the exposure necessary for any thickness of steel could be at once calculated; (2) to find the thickness of the smallest air inclusion which could be radiographed in a given thickness of steel; (3) to determine in what direction to hope for further progress; and (4) to develop the technique of, radiographing metals. In order to gain some preliminary data, several pieces of ½ -in(12.5mm.) boiler plate were obtained, 5 by 7 in. (12.5 by 17.5 cm.) in size. In one of these, holes were drilled in such a way that the axis of each hole was midway between the faces of the steel and parallel to those faces. The diameters of these holes were as follows: Hole number Diameter 1 1/4 in. = 6.3 mm 2 1/8 in. = 3.1 mm. 3 1/16 in. = 1.6 mm. 4 1/32 in. = 0.8 mm. 5 1/64 in. = 0.4 mm.

Jan 8, 1915

Jan 1, 1963

By H. S. Gieser

THE flotation of oxidized silver, ores offers an interesting problem to the operating metallurgist, who has to treat this material. The advances made in the art of selective flotation by the use of newer collectors with accelerating and inhibiting reagents suggests that there should be something to help to decrease tailing losses. For many years there was no working hypothesis, so the subject was approached more or less in the dark, but with the publication of a paper by Taggart, Taylor and Ince1 giving results of flotation tests with many organic compounds and presenting a tentative theory, a better foundation has been laid and henceforth progress should be more rapid. Over a period of one and one-half years there was much experimentation with flotation of oxidized silver ores at El Tigre, Sonora, Mexico. The material coming to the mill was straight sulfide ore in a silicified rhyolite gangue, the ore minerals being sphalerite, galena, pyrite and tetrahedrite. This came largely from the lower levels of the mine. With the approaching exhaustion of these orebodies, attention was turned to oxidized ores left behind during higher prices of silver. Of late oxidized ore has been at times 25 per cent. of mill tonnage. Aerofloat 25, in considerable quantity, together with ethyl xanthate, has been used in the mill. The former raises large quantities of "insoluble" or gangue, which is difficult to reject when the density of the tailing pulp approaches 33 per cent. solids, as it did during periods of water scarcity. The mill tailing at times contained as much as 5 oz. of silver on a 32-oz. mill head.

Jan 1, 1931

By Alan U. Seybolt

UNLIKE its sister elements, columbium (niobium) and tantalum, vanadium has not been available until recently in fabricated form. While Vanadium Corporation of America has offered the metal in fairly pure form for sale for many years in small lots for research purposes, this grade of vanadium has been brittle, probably because of a high oxygen content. Hence, when in 1950 the announcement1 was made that wrought vanadium was available as a commercial material, this represented a large step forward in the metallurgy of vanadium. While vanadium is generally regarded as a rare metal, data on its occurrence in the earth's crust show it to be as abundant as copper, zinc, and lead combined. Vanadium is widely distributed, but it does not seem to occur in massive deposits except in a few localities, principally in Colorado, Utah, and Arizona, where it is found in sandstone formations, and in Mina Ragra, Peru. Only in Colorado or Peru are ores mined solely for the vanadium content. Ores in the United States are principally carnotite and roscoelite; the former is of particular interest because of its uranium content. It is a uranium-potassium vanadate containing approximately 52 pct of UO2 and 18 pct of V2O5. Production in the United States during the war years averaged around 2000 tons a year, but dropped to 636 tons in 1946. In recent years, ferrovanadium has been selling for about $2.80 per pound of contained vanadium. This suggests that the price of the pure metal will never be as low as $2.80 per pound, but it could

Jan 1, 1953

By Albert J. Phillips

As EARLY AS 1824, Haidinger1 described crystals of native copper that were, according to Dana,2 "probably twinned parallel to the octahedral plane and normal to this axis." In 1837, Rose3 very clearly demonstrated that native copper crystals were commonly twinned on the octahedral plane. Lasaulx,4 in 1882, described polysynthetic octahedral twins and stated that enclosed twinning lamellae were observed. Even on crystals formed artificially by electrolysis, twinning was observed as early as 1886, by Brown.5 Many other descriptions of twinning in native copper and in gold and silver are to be found in the literature, and in every case with which we are acquainted the twinning is conformable to the spinel law; i. e., the octahedral plane is both twinning and composition plane. Metallurgists have long been familiar with the straight-sided bars or bands that commonly occur within the irregularly outlined grains of metallic crystalline aggregates. They are certainly found in nearly all metals of the face-centered cubic type after cold working and annealing. If a specimen showing these bands is rotated, keeping the angle of incidence of the illuminating beam constant, they usually exchange color contrast periodically with their respective matrix crystals. Also slip lines, when produced in these specimens, nearly always show a change in direction upon passing through the bands, giving rise to the "stairway" effect often illustrated in metallurgical textbooks. Apparently the only quantitative observations on bands of this sort were made by Osmond and Cartaud6 on austenitic steel. They selected,

Jan 1, 1928

By C. W. Parmalee

The ideal fuel for burning ceramic wares is the one that, among other characteristics, has little or no sulfur. For that reason wood was long considered the most desirable fuel but its high cost has practically eliminated its use except in regions where it is very abundant or other circumstances warrant its choice. The fuels commonly employed are natural and producer gas, oil, and coal. The last named is undoubtedly the most important, not only in this country but abroad. Occasionally anthracite is used but the larger part is bituminous. The quality of the coal used depends on the kind and the value of the products being manufactured. For some materials, such as common brick, hollow block, etc., the quality of the coal is of less importance than in the manufacture of polychrome terra cotta, pottery, porcelain, etc. It is obvious that in burning clays that contain notable amounts of pyrite, marcasite or gypsum, as is the case with many common clays, the sulfur content of the fuel is of much less importance. The permissible amount of sulfur in the coal used will depend on the kind of product being manufactured. "A good sample1 of coal commonly used in pottery ovens has something like this quantity of sulfur: total sulfur, 1.20 per cent.; sulfur in ash, 0.11 per cent.; volatile sulfur, 1.09 per cent." This is based on English pottery practice. Correspondence with a. number of leading manufacturers in this country has produced the following figures: Sanitary Ware.—(a) 1.0 per cent, maximum, (b) 0.5 per cent. Sewer Pipe.—(a) 1.2 per cent., (b) 1.1 per cent, present run, 3.0 per cent, has been used. Terra Cotta.—(a) 0.5 per cent, basis of contract, 1.0 per cent, approximate. Pottery.—1.0 per cent, contract, 1.5 per cent, probable content. Enameled Brick.—1.3 per cent, maximum, (a) and (6) designate different firms giving figures. Since a pottery kiln for sanitary ware will require about 14 tons of coal for a bum, the quantity of SO2 that will be generated from a 1-per

Jan 1, 1920

By Albert Phillips

As EARLY As 1824, Haidinger1 described crystals of native copper that were, according to Dana,2 "probably twinned parallel to the octahedral plane and normal to this axis." In 1837, Rose3 very clearly demonstrated that native copper crystals were commonly twinned on the octahedral plane. Lasaulx,4 in 1882, described polysynthetic octahedral twins and stated that enclosed twinning lamellae were observed. Even on crystals formed artificially by. electrolysis, twinning was observed as early as 1886, by Brown.5 Many other descriptions of twinning in native copper and in gold and silver are to be found in the literature, and in every case with which we are acquainted the twinning is conformable to the spinel law; i. e., the octahedral plane is both twinning and composition plane. Metallurgists have long been familiar with the straight-sided bars or bands that commonly occur within the irregularly outlined grains of metallic crystalline aggregates. They are certainly found in nearly all metals of the face-centered cubic type after cold working and annealing. If a specimen showing these bands is rotated, keeping the angle of incidence of the illuminating beam constant, they usually exchange color contrast periodically with their respective matrix crystals. Also slip lines, when produced in these specimens, nearly always show a change in direction upon passing through the bands, giving rise to the "stairway" effect often illustrated in metallurgical textbooks. Apparently the only quantitative observations on bands of this sort were made by Osmond and Cartaud6 on austenitic steel. They selected,

Jan 1, 1928

By Gilbert Soler

PRODUCERS of alloy steels recognize the importance of chemical composition in rela-tion to the hot-working properties and the typical surface defects found in their prod-uct. Each analysis of steel has its own peculiar characteristics. Under conditions of standard mill practice each analysis is susceptible to certain types of defects. Mill practice must be varied to obtain the best combination of surface and internal quality in the product. Chemical composition influences the cast structure and crystallization character-istics of the ingot. It also determines the rate of heating and cooling, the plastic hot-working range, and the phase structure of the steel at various temperatures as well as the tendency toward scale formation and decarburization, This paper endeavors to emphasize the manner in which chemical composition affects the various properties of steel, and to indicate the relative impor-tance of these factors in relation to the hot-working properties and surface charac-teristics of killed steel. The influence of chemical composition may be outlined as follows: I. Effect on the cast structure of steel, including: A. State of deoxidation, and type of inclusions. B. Gas content of steel. C. Freezing point and melting point of steel.

Jan 1, 1940

By Samuel S. Wyer

Magnitude and Econonmic Importance THE magnitude and economic importance of the problem of correctly valuing natural-gas leaseholds become evident when we consider that: (a) Natural gas is handled in 55 per cent. of the gas distributing plants in the United States. (b) Present known natural-gas acreage forms 47 per cent. of the total known mineral-land acreage in the United States. (c) Five acres of land are now required to protect and maintain continuous service to each of the 2,000,000 domestic natural-gas consumers in the United States. (d) The cost of acquiring and maintaining this acreage of an expendible resource represents a substantial part of the cost of the natural-gas service to the consumer. (e) "The right of a citizen by means of his ownership of or his mining leases on land to draw gas from beneath its surface is property and sometimes valuable property."1 A large number of other court decisions have established the basic legal principle that the right to drill for gas within a given area constitutes an interest in the land itself, and is necessarily an exclusive property right.

Jan 4, 1916

By E. B. Swanson

Crude oil production in Iraq during 1932 was maintained at slightly higher levels than in 1931, but the output continued to be restricted to the requirements of local consumers. The Iraq Petroleum Co., representing British, American and French interests, which has been operating within its concession east of the Tigris River since 1926, began drilling operations on Apr. 5, 1927, and completed its first well at Baba Gurgur on Oct. 14, 1927, to which area the company has since confined its drilling activities. Relatively small quantities of oil have been produced annually, but the products have been utilized in company operations and have not been offered on the Iraq market. The Khanaqin Oil Co., which has its field of operation at Naft Khana in the so-called Transferred Territories, has been supplying the Iraq market with petroleum products from Iraq wells since March 12, 1927. The output of the Khanaqin Oil Co. refinery, at Alwand, during the past three fiscal years ending March 31, has been as follows: (In Barrels of 42 Gallons Each) 1930 1931 11931 Gasoline................................. 102,940 104,571 118,012 Kerosene................................ 104,010 108,112 111,624 Fuel oil...........................1 286,9001 332,142 354,244 503,850 544,825 583,880 The Iraq Petroleum Co. has a small topping plant, with a capacity of about 150 bbl. a day, used in the manufacture of petroleum products for the company's own needs. During the 1932 fiscal year, the production was 3918 bbl. of gasoline and 2235 bbl. of kerosene, as compared with 8157 bbl. of gasoline and 6308 bbl. of kerosene during the preceding fiscal year.

Jan 1, 1933

Our merchant marine is rapidly outgrowing our consular service, according to Edward N. Hurley, Chairman of the United States Shipping Board, who urges that steps be taken immediately to provide facilities abroad for handling the millions of tons of shipping which will be afloat under the American flag in peaceful trade when the war is over. When peace is restored and our present tonnage is scattered over world trade routes, the consular service will be inadequate to handle our ships: Besides, it will have to work against the handicaps of obsolete shipping regulations and, in many cases, lack of experience. There are nearly 100 pages in the United States consular regulations dealing with shipping platters. . Many of these regulations are based on old treaties and many of them are obsolete. There are also differences between treaties with various countries. Our consuls often lack authority to handle matters involving the interests of our sailors and shipowners. Before we can operate a modern merchant marine we must revise, standardize, and simplify this whole mass of regulations and bring them up to the efficiency of other nations' practice.

Jan 12, 1918

By J. B. Cohen, M. B. Beaver, R. J. Black

RECENT investigations have shown that face-centered cubic metals may deform by twinning. Blewitt, et al' found that at 4.2"K the mode of def~rmation of single crystals of copper changed at large strains and markings formed on (111) planes. Later they- emonstrated by X-ray diffraction and metallography that the markings were twins and showed that favorably oriented single crystals of copper deformed by twinning at 78°K. They also observed twinning in silver and gold deformed at 4.2 and 78°K. Wagner3 obtained evidence for twinning from the peak shape of diffraction lines of silver cold-worked at 78°K, but twins small enough to cause such effects are not likely to be detected metal-lographically. In the work reported here lamellar structures were observed in deformed silver-gold alloys. They appeared to be mechanical twins, but metallography could not establish this conclusively. Their tendency to form depended on strain rate, temperature and composition. Specimens of silver-gold alloys (0 to 83 wt pct Au) were deformed plastically. One set was worked by hammering under liquid nitrogen, at room temperature and at intermediate temperatures. Another set was compressed slowly in liquid nitrogen to the same reductions as those produced by hammering. Tensile specimens (0.015 x 0.120 x 1.5 in.) of various compositions and approximately equal grain size (0.011 to 0.016 cm) were tested at -195°C and at room temperature. In microsections of all specimens deformed by hammering at —195°C thin lamellae appeared, Fig. 1. They were aligned in definite directions in each grain. In some grains they had two orientations. Where lamellae intersected, a displacement was apparent. Near the center of the left margin of Fig. 1 shear has taken place beyond the fully developed intersecting lamella. Many lamellae resembled Neumann bands in alpha iron. They were parallel to one side of triangular etch pits in the matrix (as in Figs. 1 and 2). The individual lamellae were narrow and had little substructure. This suggested that they did not result from concentrated local slip. The shape of etch pits within the lamellae differed from that of pits in the matrix, as can be seen in Fig. 2; this indicated a difference in orientation. Specimens slowly deformed at —195°C contained regions in which the lamellae were clustered. In these specimens some lamellae were bent and presumably had formed before the termination of the deformation. Structures of greater width than the lamellae were also seen.4 More lamellar structures formed on impact than during slow compression to a given reduction. This was true of all compositions. The structures became less abundant with increasing temperature of deformation. None was observed after extension to fracture at room temperature, but they could be pro-

Jan 1, 1959

By D. K. Crampton

NEARLY everyone who has not had the benefit of study in the field of metallurgy subscribes to a persistent and enthusiastic belief in the legendary lost art of hardening copper. This of course supplies a perfect introduction to a chapter of information on copper and its alloys, since the dissipation of fallacies and superstitions affecting an art probably constitutes the best method of getting at its real substance. Metals are hardened, but also embrittled, by a plurality of impurities. In the modern technology of copper-base metal products, we are familiar with a great host of materials, passing from one extreme of dead soft copper better than 99.9 pct pure, which in the form of wire about as thick as a match will stand hundreds of full twists in a 12-in. length, to an alloy containing less than 3 pct of alloyed substance possessing the strength of pretty good steel and capable of manufacture into razor blades, should we suddenly be deprived of steel; certainly a much better material for this purpose. Every copper alloy known to primitive man lies in some inter- mediate position and the ancient bronzes that have been found all over the world wherever an early civilization existed are usually contaminated by such impurities as sulfur, oxygen, antimony, arsenic, iron, or other materials, so that they could not possibly conform to any modern intelligent specification insuring the best combination of useful properties in alloys of their type and would go

Jan 1, 1953

Jan 1, 1968

By S. W. Miller

Most of the steel welding done at the present time is in material containing not over 0.3 per cent. carbon, and the tests here described were in similar material. These tests are not as yet completed but it is hoped that more results and more reasons for the conclusions may be presented at the meeting in February. From the time the author found the peculiar structure in electric welds referred to in a previous paper,' that is, needles or plates in the grains and similar material, in larger spots, at the grain boundaries, he has felt that these plates which may be iron nitride and probably contain some carbon, were at least partly responsible for the brittleness of electric welds. He has found but few traces of similar lines in oxyacetylene welds until the last 2 mo., he has since found large numbers under certain conditions. In the top of these welds, they are quite numerous. In the body of heavy oxyacetylene welds, they appear at times, but not nearly to the extent that they do in electric welds; the author has never seen them in the body of welds in material less than % in. (19 mm.) thick. They are shown in Fig. 82. The reason they were not noticed before is undoubtedly due to the fact that in making tests of welded pieces the weld was always ground off level with the plate, and as this structure only appears in the top 1/16 in (1-5 mm.) of the weld, they were removed by the grinding or machining; also, welds 3/4 in. thick had not been examined. It did not appear, in making bending tests, that this structure had much influence on the strength of oxyacetylene welds; while electric welds are noticeably brittle. Further, oxyacetylene welds made with certain special materials were exceedingly brittle even after the tops of the welds were removed; this was true in cases where there was no sign of the plates whatever and where the welds were remarkably free from oxide and the other usual defects. It appeared, therefore, that this brittleness did not depend on any variable that had been noticed so far, and it was decided to find where the rupture occurred in various kinds of welds made

Jan 1, 1920

By Alfred Wandke

The problem of vein formation has been of particular interest to the writer for years. As his work for a long time was confined largely to districts showing large deposits of copper ore, it was natural that the efficiency of replacement, as one if not the chief control of the emplacement of the ore, seemed a particularly attractive hypothesis. Of late years, in almost daily underground work in the Guanajuato district, he has collected evidence which makes it certain that in a number of cases the ore solutions were under sufficient pressure to force the rock walls apart and to hold them apart, thus offering an open space for the deposition of vein and ore-bearing material. This paper will concern itself with conditions frequently met with in hypogene ore deposits of the vein type, and will deal in particular with ore occurrence in precious-metal veins of the type classified by Lindgrenl as epithermal deposits, or metalliferous deposits formed near the surface by ascending thermal waters2 and in genetic connection with igneous rocks. To account for the emplacement of this type of ore deposit various writers have suggested the following agencies: 1. Shattering of the wall rocks. 2. Pressure of growing crystals. 3. Magmation, as treated at length by Spurr3. 4. Replacement. 5. Openings produced by folding. 6. Shearing due to gravity. 7. Shrinkage produced by the passage of pre-ore solutions. 8. Contraction joints produced by lateral secretion. To this list there may be added another agency, a discussion of which forms the basis of this paper: 9. Pressure of the ore-bearing solutions.

Jan 1, 1931