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By E. C. Carris

THE particular field of application of machines utilizing air cur¬rents as the primary separating medium is in the cleaning of the fine sizes of bituminous coal. Approximately 12,000,000 tons of bituminous coal were cleaned by air machines during 1940. They have not found any application for cleaning anthracite. Since the development and introduction of the first successful com¬mercial pneumatic oscillating machine for cleaning bituminous coal in 1916, by the Sutton, Steele and Steele Co., Dallas, Texas, and the Ameri¬can Coal Cleaning Corporation, formerly of Welch, W. Va., four other successful pneumatic coal-cleaning machines have been developed and introduced to the American coal-mining industry: 1. Peale Davis: "Pneumo-Gravity" machine, 1924. 2. Arms "Concentrator," oscillating table, 1924. 3. Heyl and Patterson oscillating table, 199.7. 4. "Stump Air-Flow," pulsating air jig, 19391. Out of these five developments only the Sutton, Steele and Steele, or American Oscillating, and the Stump Air-Flow Jig remain on the market. They are the predominating pneumatic coal-cleaning machines in use in the United States. HISTORY OF AMERICAN TYPE SEPARATOR The first successful American machine, the CJ table (Fig. 1) was developed by the Sutton, Steele and Steele Co. The SJ table was the first standard model designed specifically for the cleaning of coal. It was installed in the original Crane Creek plant, owned and operated by the American Coal Co. at McComas, West Virginia. This plant was designed by The Roberts and Schaefer Co., Chicago, Ill., working in cooperation with the American Coal Cleaning Corpora¬tion, which had taken over the patent rights and sale of the pneumatic separators. Eight machines were installed in this plant. They were known as the type SJ. They were 60 by 84 in., the short dimension being the width of

Jan 1, 1943

By F. C. Farnham

THERE has been very little, if any, uniformity in the reference datum used for magnetometer surveys. It has been the practice to choose a base station at which the magnetic field is assumed to be normal and call the difference in field strength between a given station and this base the anomaly at the given station. For small-scale surveys latitude and longitude corrections may or may not be applied, but for large-scale surveys such corrections usually are applied. The United States Coast and Geodetic Survey maps showing lines of equal magnetic intensity are commonly used to determine the normal latitude and longitude variation by scaling values from the map for given points and computing the change per mile north and the change per mile east. This method has been quite satisfactory for isolated surveys, but when two surveys originating at different base stations were extended until they joined, difficulty arose, not only because of discrepancies between base-station values, but also because of differences between the latitude and longitude correction factors used for the separate surveys. It is the purpose of this paper to describe a reference datum for magnetometer surveys which, it is believed, will eliminate most of the difficulty arising from this source. In order to be satisfactory, a general datum for magnetometer sur-veys should be as close as possible to the observed field and still he based on some assumed distribution of magnet poles, in order that the "normal" value of any component of the field for any given point may be computed to as many significant figures as desired. Such a field has been com-puted, and a comparison of the intensity of its vertical component with the average vertical intensity for the United States as shown by the U.S.C.G.S. map of lines of equal intensity for 1935 is shown in Fig. 1.

Jan 1, 1939

By R. P. Rothwell

THE first difficulty mentioned is that in some instances two or more beds of coal separated by sandstone or slate rocks of considerable thickness in one part of a basin, are found running together in another part. Of course, we may happen to strike first the part of the basin where there is but a single seam, and in this case the bed would appear to divide into two or more branches within a short distance. Such cases are not rare in the anthracite coal-fields. I would suggest as an explanation of this phenomenon the gradual sinking of the peat-marsh-the embryo coal-bed-on one side, and the moving forward of the marsh, so that on one part of the bed the formation of peat would still be progressing, while another part, being under water, would be covered with mud and sand. Thus we have different portions of the same bed of different ages. Now if the sinking of the marsh be stopped for a time, the bed will become thicker in the portions left exposed, and if the sinking now changes in direction, so that the part that had previously gone down com¬mences to rise, we should have the phenomenon of a bed, continuous throughout, with one portion overlying another, and separated from it by rock strata. These are exactly the conditions observed in splitting beds. While one side of the lake is sinking, and the peat-marsh moving on in that direction, the other side may be rising,

Jan 1, 1873

By A. A. Berk

LAGGING technology and the slow spread of information have been the chief obstacles to widespread participation in minimizing the industrial pollution load. These obstacles can be conquered by fact finding and applied research. There are three aspects to the problem of water-borne mineral waste: to minimize the amount being thrown away, to select a predisposal treatment, and to use the products or dispose of them. It is often possible to minimize the waste by making very minor changes in the process that produces it. For example, a manufacturer of automobile bumpers greatly reduced the dragout 'from a plating bath by modifying the design and position of two boltholes.' A plater of automobile hubcaps installed a drainage bar and decreased the loss of chrome-plating solution to the rinse water by about 80 pct.' The mill at a western mine found it possible to discard 60 to 70 pct of an ore with minimum treatment," so that the processing effort could be concentrated on a high-graded slime, with significant reduction in costs and improvement in recovery. The possibilities for waste reduction through process changes are limited only by the imagination. A recent patent points out the advantages of using No. 1 fuel oil instead of water in wet-process cement making;& the fuel oil presumably has better properties than water for this purpose and is said to be almost com'pletely recovered or utilized, so that there is no waterborne waste. Recycling to reduce wastes and improve process economy is very well illustrated in vanadium and uranium recoveries from relatively low grade ore. Ores containing 6 pct calcium carbonate were found to give poor vanadium recovery by the salt-roasting process because the vanadium was converted to water-insoluble calcium vanadate. Following the salt-roasting process, sulfuric acid was used to leach the uranium. Enough calcium sulfate was formed

Jan 1, 1958

By C. E. McCarthy, A. George Stern, Stanley J. Green

THE national interest prompts consideration of any new source of mineral wealth even though the immediate need may be of minor importance. A critical shortage of potash in the United States during the World War of I9I4-I8 stimulated broad development, which established an American potash industry on a basis so sound that this commodity is not even listed as urgent in the present war program. However, this should not minimize its importance, and the need remains, not only for adequate supplies of the usual potash salts (the chloride and the sulphate) but of all potash chemicals. Potassium carbonate (known commercially as pearl ash) has been a high-cost commodity; in consequence, the quantity used by industry has been relatively small. By a combination of fortuitous geographical circumstances, there is opportunity to produce a low-cost potassium carbonate with the possibility that this might become an important source of chemical potash. The following paper considers a recently developed process1 taking advantage of these conditions. WYOMINGITE DEPOSIT For many years it has been known that a deposit of potash-bearing igneous rock known as wyomingite occurs in the southwestern part of Wyoming at Zirkel Mesa, which is 44 miles northeast of the town of Green River (Fig. I). The western escarpment of this deposit is about 3 miles east of the Superior Branch of the Union Pacific Railroad. This mesa alone covers approximately 3300 acres, and the average thickness of the wyomingite flow is 75 ft. It has been estimated2 that about one billion tons of wyomingite occur in this one deposit, all of which can be mined by open quarrying without overburden. In addition, there are several smaller deposits within 10 miles, so that the aggregate wyomingite in the area approaches two billion tons. This is one of the world's largest sources of leucite, and the only known deposit of its kind in the United States. The wyomingite (which is in the form of a lava flow and numerous small craters), with the mineral leucite as its most important component, has a mineral composition3 of: leucite, 50 per cent; phlogopite, 15; diopside, I2; kataphorite, 15; glass and apatite, 8. The phlogopite is present in visible phenocrysts 1/8 to 1/2 in. in diameter, but the leucite usually is almost microcrystalline and not capable of liberation by grinding. Chemically, the wyomingite has a potash content averaging slightly higher than eleven per cent K20. The potash is mainly in the leucite, but part of it is in the phlogopite and a small amount is in the feldspars that are occasionally seen as undigested occlusions of the granite country rock, through which the leucite-bearing lava intruded, and as sanidine feldspar both in the crystalline and glassy phases of the rock. A typical analysis of the wyomingite from Zirkel Mesa is as follows:

Jan 1, 1944

By C. E. McCarthy, A. George Stern, Stanley J. Green

The national interest prompts consideration of any new source of mineral wealth even though the immediate need may be of minor importance. A critical shortage of potash in the United States during the World War of 1914-18 stimulated broad development, which established an American potash industry on a basis so sound that this commodity is not even listed as urgent in the present war program. However, this should not minimize its importance, and the need remains, not only for adequate supplies of the usual potash salts (the chloride and the sulphate) but of all potash chemicals. Potassium carbonate (known commercially as pearl ash) has been a high-cost commodity; in consequence, the quantity used by industry has been relatively small. By a combination of fortuitous geographical circumstances, there is opportunity to produce a low-cost potassium carbonate with the possibility that this might become an important source of chemical potash. The following paper considers a recently developed process1 taking advantage of these conditions. Wyomingite Deposit For many years it has been known that a deposit of potash-bearing igneous rock known as wyomingite occurs in the south- western part of Wyoming at Zirkel Mesa, which is 44 miles northeast of the town of Green River (Fig. I). The western escarpment of this deposit is about 3 miles east of the Superior Branch of the Union Pacific Railroad. This mesa alone covers approximately 3300 acres, and the average thickness of the wyomingite flow is 75 ft. It has been estimated2 that about one billion tons of wyomingite occur in this one deposit, all of which can be mined by open quarrying without overburden. In addition, there are several smaller deposits within 10 miles, so that the aggregate wyomingite in the area approaches two billion tons. This is one of the world's largest sources of leucite, and the only known deposit of its kind in the United States. The wyomingite (which is in the form of a lava flow and numerous small craters), with the mineral leucite as its most important component, has a mineral composition3 of: leucite, 50 per cent; phlogopite, 15; diopside, 12; kataphorite, 15; glass and apatite, 8. The phlogopite is present in visible phenocrysts 1/8 to 1/2 in. in diameter, but the leucite usually is almost microcrystalline and not capable of liberation by grinding. Chemically, the Wyomingite has a potash Content averaging slightly higher than eleven per cent K2O. The potash is mainly in the leucite, but part of it is in the phlogopite and a small amount is in the feldspars that are occasionally seen as undigested occlusions of the granite country rock, through which the leucite-bearing lava intruded, and as sanidine feldspar both in the crystalline and glassy phases of the rock. A typical analysis of the wyomingite from Zirkel Mesa is as follows:

Jan 1, 1948

By A. George Stern, Stanley J. Green, C. E. McCarthy

The national interest prompts consideration of any new source of mineral wealth even though the immediate need may be of minor importance. A critical shortage of potash in the United States during the World War of 1914-18 stimulated broad development, which established an American potash industry on a basis so sound that this commodity is not even listed as urgent in the present war program. However, this should not minimize its importance, and the need remains, not only for adequate supplies of the usual potash salts (the chloride and the sulphate) but of all potash chemicals. Potassium carbonate (known commercially as pearl ash) has been a high-cost commodity; in consequence, the quantity used by industry has been relatively small. By a combination of fortuitous geographical circumstances, there is opportunity to produce a low-cost potassium carbonate with the possibility that this might become an important source of chemical potash. The following paper considers a recently developed process1 taking advantage of these conditions. Wyomingite Deposit For many years it has been known that a deposit of potash-bearing igneous rock known as wyomingite occurs in the south- western part of Wyoming at Zirkel Mesa, which is 44 miles northeast of the town of Green River (Fig. I). The western escarpment of this deposit is about 3 miles east of the Superior Branch of the Union Pacific Railroad. This mesa alone covers approximately 3300 acres, and the average thickness of the wyomingite flow is 75 ft. It has been estimated2 that about one billion tons of wyomingite occur in this one deposit, all of which can be mined by open quarrying without overburden. In addition, there are several smaller deposits within 10 miles, so that the aggregate wyomingite in the area approaches two billion tons. This is one of the world's largest sources of leucite, and the only known deposit of its kind in the United States. The wyomingite (which is in the form of a lava flow and numerous small craters), with the mineral leucite as its most important component, has a mineral composition3 of: leucite, 50 per cent; phlogopite, 15; diopside, 12; kataphorite, 15; glass and apatite, 8. The phlogopite is present in visible phenocrysts 1/8 to 1/2 in. in diameter, but the leucite usually is almost microcrystalline and not capable of liberation by grinding. Chemically, the Wyomingite has a potash Content averaging slightly higher than eleven per cent K2O. The potash is mainly in the leucite, but part of it is in the phlogopite and a small amount is in the feldspars that are occasionally seen as undigested occlusions of the granite country rock, through which the leucite-bearing lava intruded, and as sanidine feldspar both in the crystalline and glassy phases of the rock. A typical analysis of the wyomingite from Zirkel Mesa is as follows:

Jan 1, 1948

By Arthur F. Wendt

The following experiments and researches were originally conducted by Dr. Heinrich Rcessler, chief of the German Gold and Silver Parting Establishment at Frankfort-on-the-Main, for the sole purpose of abating the nuisance created by the discharge into the air of the sulphurous and sulphuric acids generated in the process of parting bullion by sulphuric acid. The results achieved have, however, an important bearing not only on this process, but are of value in the manufacture of sulphuric acid and sulphate of copper from sulphurous gases derived from any source. It has now been in successful operation for a term of years at Dr. Roessler's own works, and has been lately introduced with satisfactory results at the royal mints of Kremnitz and Munich, and the well-known establishment of Johnson Mathey & Co., of London.

Jan 1, 1884

By C. A. Heiland

THE investigations described were made on a portion of Clear Creek basin near Golden, Colo. (A portion of the area under survey is shown in Fig. 1. The photograph was taken in the vicinity of station No. 2 of Line II.) Three principal purposes were in the minds of the investigators: 1. To repeat with modern, more sensitive and more reliable instruments magnetometric placer investigations previously made. 2. To disprove the recently advanced theory that deposits of the glacial period have no pronounced magnetic effects. 3. To develop in detail the theory of the magnetic effects produced by placer deposits. Six years ago, the first magnetic observations were published, which proved that it is possible to locate gold-bearing channels with relatively crude instruments.1 Two years ago, K. C. Laylander published results obtained with similar instruments.2 The measurements of the latter were discussed by the senior author of this paper.3 At that time, however, the material available for such a discussion was somewhat scarce and not made with the most modern magnetic instruments, although very brilliant results were obtained. Therefore, the senior author felt that magnetic investigations should be made on very clear geologic conditions with the most modern instruments.

Jan 1, 1928

By J. J. Kramer, W. A. Tiller, G. F. Bolling

The temperatures of solid-liquid interfaces have been measured during the growth of Sn-Pb alloy crystals which exhibited a cellulur substructure. A simple descriptive theory was used in combination with this data and the other measurable growth variables to predict some features of the solute segregation such as the intercell excess concentration and the depth of cell grooves during freezing. The effective distribution coefficient at the tip of a cell, a, was predicted and experimentally found to vary in the range, 1 >a > k0. At the lower limit, the severe segregation that must arise between dendritic cells was substantiated by various observations such as the existence of a second Phase even for alloys of only 0.2 wt pct Pb. ThE cellular morphology of a solid-liquid interface is known to coincide with the formation of a zone of constitutional supercooling ahead of the interface during growth.' The occurrence of various cell structures, (two-dimensional cells, regular cells, dendritic cells), has been quantitatively investigated,'2,4 but the segregation of solute which arises as a consequence of this mode of growth has only been examined qualitatively. An indirect method of obtaining the solute concentration at the tip of a cell cap during solidification has been de-

Jan 1, 1963

The Honor Roll includes the names of all members of the Institute whom we know to be on active military duty at the date of its compilation, February 7, 1918. We are aware that there are many others of whose activities we have not been informed, and we shall be grateful for information as to any such omissions from the Roll. 1. MEMBERS ON ACTIVE MILITARY SERVICE Mail addressed to members on the first division of the Roll and sent to the office of the Institute Will be forwarded according to the best of our knowledge at the time. AARONS, J. BOYD, Capt., 4th Reinforcements, 11th Infantry, Australian Imperial Force. '05 ADAMS, HENRY, Capt Asst. to Dept. Engr., Northeastern Department. '02 AGNEW, FRANK VANS '04 ARBE, FREDERICK R., Capt 33d Engineers. '97 ALDER, ALFRED Engineers' Reserve Corps. '17 ALFORD, NEWELL G., Sgt., Bureau of War Risk Insurance, Headquarters 84th Division. '14 ALLEN, HEMAN H., Private Co. D., 8th Reserve Engineers. '17 AMBLER, HARRY A., Lieut 30th Infantry. '16 ANDERSON, ALEXANDER, Lieut Royal Garrison Artillery. '07 ANDERSON, GEORGE K., JR., See. C, 1st Co., 3d Officers' Training Camp. '17 ANDREWS, CLARENCE W., 1st Infantry Co., Officers' Training Camp, 83d Division. '13

Jan 1, 1923

FOLLOWING the presentation at the annual meet-ing of the paper "Recent Developments in Classi-fication," by A. M. Gaudin and W. L. Remick, the discussion presented below took place: H. N. Spicer : I haven't been able to study this paper closely, but I would like to ask 'Mr. Remick something regarding the work done by the mechanical classifier. The screen test given here would appear to show that the classi-fier did very, very poor work. The 44 per cent efficiency calculated from this equation is much lower than any ordinary operation. Nothing is stated regarding the de-tails. of the operation, the slope of the classifier, the dilu-tion, the speed, and such other factors that influence results. I would also like to know something of the material that was worked. The Manhattan schist that I have seen them digging out of the subways is of a flaky nature, so that in any classifier, you might get the factor of fine flakes floating over. Was the same material used in the hydrotator test? The screen tests vary a whole lot. Mr. Remick: You will notice the Dorr classifier han-dled the circulating load. This classifier naturally was run in closed circuit. I should like to be pardoned for quoting from Mr. Bates' paper of last year on "Classifica-tion in the Witwatersrand Mills." In this report only two efficiencies were given for the so-called straight type Dorr classifier. One was 44.6 per cent and the other 61.6. I don't know whether or not an average should be taken for the proper performance. I assume that that test was performed under better conditions, yet the efficiencies av-eraged only 53.1 per cent. I am afraid I am taking the words out of Professor Taggart's mouth, but he has told me that the Dorr classi-fier at Columbia is not the proper size to work with the Hardinge mill with which it is connected. This indicates only the inadvisability of putting commercial sized mat chines in a school laboratory. You cannot, he says, get the proper tonnage from the Hardinge mill to work the Dorr classifier and get the best results. Mr. Bates' results show higher efficiency with the lower capacity. Now, on the other hand, I assume that the classifier described in Mr. Bates' paper was probably run at the proper capacity.. It is a rather puzzling question.

Jan 4, 1927

FROM north to south activity is picking up through- out the Labrador Trough-already shown to be one of the world's great iron ore provinces. Center of current activity and interest lies in the mid-southern part of the trough as drills, equipment, and . . . money start to pour into the area near Mt. Wright and Wabush Lake. First major announcement in the area came early this spring when J&L and CCI outlined an estimated billion-ton deposit for "future" operations. Later impetus came from rumored railway for US Steel's Quebec Cartier projects in the Mt. Reed area slightly to the south. As this issue went to press US Steel's request for bids on railway and hydroelectric construction, plus IOCC's decision to step up the time- table on its program in the Wabush Lake area east of Mt. Wright, triggered a flurry of other announcements involving many of the top U. S. and Canadian iron ore firms. Do not look for most of these place names in the average atlas . . . they aren't there yet, but they soon will be.

Jan 6, 1958

By John Griffen

K. F. Tromp (Kerkrade, Holland)—Your assumption that the Dutch State Mines have lead in the development of heavy medium processes—the Barvoys, Loess, Driessen—is not correct. The credit should be given to a Dutch engineer Mr. deVooys, the inventor of the Barvoys process. deVooys started in 1932 in Hiickelhoven, a German but Dutch-owned mine, where he was a director. Several plants on the Continent as well as in Great Britain were erected. The State Mines started their first plant in 1937. They could not get that plant working satisfactorily and built another one. Their process made no headway, and up to 1946 there was only one plant installed, the one at their own pit. Since 1946 they started the cyclone process and only since that time have they been more active, though industrial cyclone washeries are still in their infancy. deVooys sold his patents to the Dutch State Mines in 1946 and this might have given you the impression that the pioneer work had been done by the Dutch State Mines. John Griffen (author's reply)—I wish to thank Mr. Tromp for giving the correct story on the development of heavy medium processes in Holland.

Jan 1, 1952

By GEO H. DEIKE

NOT much activity has been evident during the past year in the establishment of co-operative scholarships but the interest among the coal-mining companies is more pronounced than ever. This is apparent from the replies received to a letter sent out by the Committee on the Promotion of Student Interest in Coal Mining to over 120 coalmine operating officials. With that letter was forwarded a bulletin issued by the school of mineral industries of The Pennsylvania State College entitled ?Industrial Scholarships ? a Partnership of Industry and Education.? In that circular was outlined the need for trained men in the war and postwar world, and particularly as such demands pertain to the growth of the mineral industries.

Jan 1, 1943

By W. F. Holbrook, C. E. Wood, E. P. Barrett

THE high-frequency laboratory induction furnace with a rotating liquid crucible enables research workers to conduct certain investigations heretofore very difficult or impossible to realize because vessels are not obtainable that are capable of resisting the physical conditions or the chemical actions to which they are subjected. Applications for patents covering commercial uses of centrifugal liquid crucibles were filed in the United States in 1919,1 in France in 1925, in the United States and Germany in 1926,2 and in France in 1927.3 In 1928, Schuette and Maier,4 of the Bureau of Mines, reported the construction of a whirling table beneath a high-frequency induction furnace. SHAPE AND SIZE OF CENTRIFUGAL LIQUID CRUCIBLES When a vessel containing a liquid is rotated, the inner surface of the liquid takes the shape of a paraboloid under the simultaneous action of centrifugal force and gravity. The internal dimensions of the paraboloid rotating liquid crucible are governed by the diameter of the container and .its speed of rotation. Melted Wood's metal was poured into cylinders 2 1/2 in. in diameter, which were rotated at 180, 300, and 468 r.p.m. When the metal was solid, a slurry of plaster of Paris was added, and rotation continued until the plaster had set. Fig. 1, a photograph of sections of the cylinders, shows the effect of speed of rotation of the containers upon the shape of the inner surface of the rotating liquid crucibles. TYPES OF FURNACES Three types of high-frequency induction laboratory furnaces using liquid-metal crucibles were designed and constructed by the Blast

Jan 1, 1938

By R. J. Quigg, G. S. Doble

Commercial stress -relieved TD Nickel bar was shown to retain room- and elevated-temperature tensile strength after exposure up to 2501°F. Cold swaging increased both room -temperature and 2000°F tensile strength. After annealing at 2500°F the strengthening due to swaging was retained at 2000°F hilt eliminated at room temperature. Annealing produced changes in hardness and X-ray half peak width indicating the presence of recovery processes as 1071° as 1000°F but no recrystallization of swaged material was noted at any temperature. In contrast to swaging, rolling induced a recrystal-lized structure after annealing. The tensile strength of this recrystallized structure was comparable to the cold-worked condition. High-temperature tensile properties of as -received bar were highly anisotropic with the transverse tensile strength being one fifth the longitudinal value. The aniso-/ropy is affected by working direction and may he partially reversed by changing the direction of metal flow. The divergence in tensile strength, beginning above 550°F or- approximate one third the absolute melting point, is strain-rate dependent. T D Nickel is a commercial dispersion-hardened alloy containing 2 vol pct thoria. The dispersion, consisting of spherical particles 0.030 to 0.050 in diameter with an interparticle spacing of less than 1 is reported to maintain stable properties up to 2400°F.1 This stability of second phase results in maintenance of elevated-temperature strength at higher temperatures and longer times than normal nickel-base superalloys.2 The purpose of this paper is to describe the effect of various mechanical working operations on the strength and microstructural stability of TD Nickel bar. MATERIAL AND PROCEDURES All material used in this study was commercial TD Nickel bar. This material is produced by a chemical process which results in a nickel powder containing a dispersion of thoria particles. The powder is then pressed, sintered, extruded, and subsequently worked to bar stock. Three starting materials from three separate lots were used: as-extruded bar. 1-in.-diam stress-relieved bar, and 1/2-in.-diam stress-relieved bar. Since TD Nickel bar stock is cold-worked without a recrystalliza-tion anneal, the accumulated deformation or degree of cold work in these materials increases as the bar diameter decreases. Some of the 1/2-in.-diam bar was swaged to 1/4 in. diameter at room temperature in order to produce an as-worked condition for comparison with the stress-relieved stock. Tensile testing was performed on an Instron Tensile Tester at a constant crosshead speed of 0.020 in. per min. The 0.2 pct offset yield strength was measured from the load-crosshead movement plot. Specimen gage dimensions were 0.080 in. in diameter by 0.40 in. in length, producing a strain rate of approximately 0.050 min-1. Specimens were tested in air and heated within a resistance-wound furnace controlled to ±5°F. A 15-min soak at temperature was employed before testing. Samples were heat-treated in air and specimens machined after exposure with sufficient material removed to eliminate any surface contamination. X-ray line breadth was determined from a diffractometer scan of a transverse face of a bar using copper K, radiation. Metallographic preparation utilized standard mechanical polishing with Carapella's etch. Specimens for electron microscopy were electropolished in a 1:7 sulfuric/methaol solution and chromium-shadowed collodion replicas prepared. RESULTS AND DISCUSSION I) Effect of Elevated-Temperature Exposure on the properties of TD Nickel. The effect of various elevated-temperature exposures on the room-temperature tensile strength of TD Nickel is shown in Table I. In the unexposed condition the tensile strength, reduction in area, and hardness all increase with increasing accumulated deformation while the elongation decreases. After exposure at 2500°F the strength of all three materials decreases to about 65,000 psi and the elongations increase slightly. The apparent increase in strength of the 1-in. bar after a 2000°F treatment is probably experimental scatter. These results indicate that the room-temperature strengthening due to additional deformation is annealed out upon elevated-temperature exposure. In contrast to the room-temperature data, the 2000°F tensile strengths increase in order of increasing deformation even after exposure. Although some loss of strength occurs after exposure, much of the effect of working is still maintained at 2000°F. The room-temperature hardness after various

Jan 1, 1965

All the TECHNICAL PUBLICATIONS and CONTRIBUTIONS published in 1935 are available at Institute headquarters, unless otherwise noted. They are also on file in many public, university and technical libraries and, when so indicated in the list, may be found in the TRANSACTIONS. Copies of the TECHNICAL PUBLICATIONS have been mailed to members of the Institute that are registered in the different classes: A-Metal Mining; B-Milling and Concentration; C-Iron and Steel Division; D-Nonferrous Metallurgy; E-Institute of Metals Division; F-Coal Division; G-Petroleum Division; H-Industrial Minerals Division (Nonmetallics); I-Mining Geology; J-Mineral Industry Education Division; K-Mining Administration; I-Geophysical Prospecting. Other members may obtain copies by writing to the Secretary. Copies of CONTRIBUTIONS may also be obtained from the Secretary's office. Additional copies are sold at the rate of 1 cent per page; minimum charge, 25 cents. Nonmembers may purchase the papers at the prices mentioned. [ ]

Jan 1, 1936

All the TECHNICAL PUBLICATIONS and CONTRIBUTIONS published in 1934 are available at Institute headquarters, unless otherwise noted They are also on file in many public, university and technical libraries and, when so indicated in the list, may be found in the TRANSACTIONS Copies of the TECHNICAL PUBLICATIONS have been mailed to those members of the Institute who are registered in the different classes A-Metal Mining, B-Milling and Concentration; C-Iron and Steel Division; D-Nonferrous Metallurgy; E-Insti¬tute of Metals Division; F-Coal Division; G-Petroleum Division; H-Nonmetallic Minerals; I-Mining Geology; J-Mineral Industry Education Division; K-Mining Administration; L-Geophysical Prospecting Other members may obtain copies by writing to the Secretary Copies of CONTRIBUTIONS may also be obtained from the Secretary's office Additional copies are sold at the rate of 1 cent per page, minimum charge, 25 cents Nonmembers may purchase the papers at the prices mentioned

Jan 1, 1935

By Philip Kraft

WHEN it came time to write a biography of Philip Kraft, we got out a copy of Bartlett's "Familiar Quotations" and looked through the references to Travel, Traveled, Traveler, and Traveling, feeling sure there would be some reference to Mr. Kraft. Sure enough, we found: "Travel, in the younger sort, is a part of education; in the elder, a part of experience." Had Francis Bacon done his writing three and a half centuries later, Mr. Kraft might well have served as the inspiration for that sentence. New Yorker born, he received his B.S. and E. M. degrees from Columbia. In 1912, then 22 years old, he took off for Germany where he spent two years studying at the Royal School of Mines, Berlin, for his Doctor of Engineering degree. Contrary to the Greeley-Soule precept, Mr. Kraft, on his return from Europe, went north to South Porcupine. Ont., working as geologist and mining engineer for the Dome Mine. From South Porcupine his next stop was Washington, D. C., where, during the years the country was in the first World War, he was engaged in war work.

Jan 1, 1947