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By DR. RICHARD RATHBUN

ON behalf of the Regents and the Secretary of the Smithsonian Institution, it gives me great pleasure to welcome you to the National Museum; but it is to your own museum, since it belongs to you in common with all the people of the country. Still young in a life which has been beset with many difficulties, it has gathered strength and attained a growth quite unprecedented. In fact, it is this very growth which has been the chief cause of trouble, always leading far and away beyond the capacity for storage ; and to-day there is nearly as much material contained in outside buildings as is displayed in this one. You will, accordingly, find the collections crowded, the cases so close together that their contents are often difficult to view, and the arrangement generally lacking symmetry. You may, therefore, be inclined to regard us as poor custodians of the collections of a great nation, but I beg you to withhold your judgment for a while. From the beginning there has been abundant zeal and activity and a proper direction of affairs, but space and money have been lacking. There is now a prospect of better times. All about you here is a beautiful park, but without. a covering it is not adapted to museum purposes. Upon it, however, a new large building is going up, so extensive in its dimensions that technology can soon be given a fitting home, thus realizing one of the earliest aspirations of the Regents. Some sixty-five years ago the extensive returns of specimens from the famous Wilkes Exploring Expedition around the world began to reach Washington, where they were deposited in the Patent Office Building, and formed practically the first of the National Collections. Six years later the Smithsonian Institution, based upon the bequest of James Smithson, was

Jul 1, 1905

By W. L. Hill, W. H. Armiger, S. D. Gooch

The physical properties, chemical behavior under thermal treatment, and fertilizer value of fluorine-containing pseudowavellite (hydrous calcium aluminum phosphate) that occurs as phosphate clay admixed with quartz sand in an extensive deposit near Bartow, Fla., were determined by experiments in laboratory, pilot-plant, and greenhouse. When the mineral was heated at 500°C, 80 pct of the phosphorus became citrate soluble. The heated product, however, deteriorates markedly under moist conditions such as obtain in the soil.

Jan 1, 1950

By COURTNEY DE KALB

IRON ore is the cause of the present trouble in Morocco. At least three nations are interested in the outcome and private syndicates have been active. The iron deposits are found in that mountainous northern coast line known as the Rif. This is an uplift that has been cut through, by the northward drainage, representing an ancient land surface. Erosion has produced .a fiordlike coast, which circum- stance has aided contraband' traffic to the tribes dominated by Abd-el-Krim, the chief of the clan of the Beni Urriaguel, near the center of 'the north coast, opposite Alhucemas. The iron deposits are extensive in the territory of the Beni Urriaguel. They were "located," if such a term is permissible, many years ago. The first arrangements, through direct contracts with the tribal chieftains, have been reinforced by compliance with the subsequent code under the Spanish protectorate in 1914. Under those terms, the location had to be made through the Arbitral Commission sitting in Paris. These locations, or "denouncements," were made by the I-louse of Mannesmann, of Hamburg.

Jan 1, 1925

E. K. Landis, Philadelphia, Pa. (communication to the Secretary) : Mr. Firmstone's paper is of great interest; but he has unfortunately otnitted to state the most important point, viz., the percentage of sulphur in the two materials he compares; and this omission vitiates the conclusions which he draws. Comparing by grade, instead of silicon-contents (as in his Table III.), the iron made using limestone with that made using dolomite, we find for gray-forge the average of four analyses under limestone to be, Si, 0.644; S, 0.089 ; while one analysis under dolomite gives Si, 0.508 ; S, 0.070. For No. 2 iron, the limestone flux gives, as an average of 19 analyses, Si, 1.107; S, 0.051; while the average of 4 analyses made with dolomite flux gives Si, 0.630; S, 0.056. It will be observed, that no No. 1 pig is given under limestone, while 14 analyses appear under dolomite, averaging Si, 0.950 ; S, 0.028. As nothing is said about changed conditions, it is Fair to presume that the ore and fuel, as well as the blast-temperature (which is stated to have been uniform at about 750' F.) remained practically the same; and since the sulphur in the two fluxes is not given, it is impossible to know whether the lower sulphur for equal silicon-contents is due to the use of dolomite or to other conditions. The use of dolomite would produce a more fusible cinder, and the furnace would be hotter than when using limestone; therefore, we might expect to see a grayer iron. The amount of So. 1 iron made with dolomite seems to confirm this supposition; and, under these conditions, we might expect more of the sulphur to be volatilized, and to pass off in the gases. The easier fusibility of the cinder would also permit more rapid driving; and this should reduce the amount of silicon and sulphur in the iron, as the amount of reduced metalloids in the pig is directly proportional to the length of time it remains in the reducing-zone.

Jan 1, 1895

By James Douglas

IN discussing the waste upon which hinges, or is supposed to hinge, so largely the preservation of our national resources, the conclusions reached would be more reliable if actual ex¬perience were consulted, and fewer deductions were drawn from general statements, which are often the product of the imagination. It cannot be questioned that the value of by-products has not been sufficiently appreciated by us, and that our, tardiness in recovering the useful ingredients of the escaping gas of our coke-ovens is one of the most glaring instances of shortcoming in that direction. And yet even for that sin there is some palliation in the immature condition of affiliated industries. I presume that it is admitted, without argument, that, except under very exceptional conditions, all the elements cannot be recovered from most of the ores or natural products. which we treat. While it is a shame that the by-products from our coke-ovens should be dissipated, Edward W. Parker's report to the U. S. Geological Survey for 1906' supplies a fairly good excuse in justification of this appalling waste. He says (pp. 773 to 774.)

May 1, 1909

By Wittenau, E.

OPERATION of a pilot mill of 100 tons' daily capacity during 1930 and 1931 proved that the copper minerals of the Colorado and Clay sections of the Morenci ore body could be successfully concentrated by the flotation process. Economic conditions caused postponement of further testing work until late in 1938 when the former No. 6 Concentrator at Morenci was converted into an experimental mill of 1500 tons' daily capacity which was known as the Test Concentrator. The Test Concentrator began continuous operation on April 3. 1939, using such crushing and grinding equipment of the No. 6 Concentrator as was appropriate. Modern classifiers and certain flotation machines were installed and later other types of flotation machines, a large grate-type grinding mill. mechanical screens, a short-head cone crusher, and a disk filter were added to the test equipment. Operation was uninterrupted until Dec. 31, 1941.

Jan 1, 1942

By W. H. Bassett

BERYLLIUM was discovered in 1798 by Vauquelin and the metal was first produced by Wohler in 1828 about a year later than his production of metallic aluminum. Beryllium remained dormant until about 1920 when the production of the metal by the electrolysis of a molten bath was carried out by Stock in Germany, closely followed by Dickinson in the United States and by Vivian in England. This may not have been the first time the electrolytic method was thus used but was the beginning of present-day methods. I believe the first commercial attempts in this country started with the Kemet Laboratories about 1924. Siemens & Halske in Germany were working on the same problem at about the same time. The work of the Kemet Laboratories was transferred to the Beryllium Company of America and later to the Beryllium Development Corporation. In 1926 1 made a considerable study of the beryllium¬copper alloys, using beryllium purchased from the Beryllium Company of America, and read a paper on this subject at the February, 1927, meeting of the A.I.M.E. However, I failed at that time to discover the properties of precipitation hardening which such alloys have in a very marked degree. After this publication the work on beryllium-copper alloys rested awhile. One cause for this was the difficulty of securing a supply of beryllium-at least at what might be considered a reasonable price. In 1926 the price was $200 per lb., a figure which held about the same both in this country and in Germany until the beginning of 1932, when it was offered here at $50 per lb. if taken in the form of a copper alloy which carried about 121/2 per cent beryllium. Somewhat later the 121/2 per cent alloy dropped to $25 per lb. of beryllium contained, which is the present price. Promise is made that with a greater consumption, production on a larger scale warrants a reduction in price to $10 per pound or less.

Jan 1, 1933

By Dilip K. Das, Douglas T. Pitman

ONE of the major uses of barium in metallic form is as a getter material in vacuum tubes. Because of the high chemical reactivity of the metal, Ba-Al alloys are extensively used. Numerous methods for the preparation of Ba-Al alloys have been published, a few of which1-4 are cited here. Most of these methods were found to be quite elaborate, involving the reduction of BaO, and not too well adapted for the close control of the final composition of small amounts of alloys prepared for laboratory use. A simple laboratory method for the preparation of Ba-A1 alloys in small batches starting from pure metals was devised, so that it was possible to control the desired compositions to within 1 pct. The pertinent features of the alloy system Ba-Al5 are 1) an intermediate compound BaAl, with the melting point of 1050°C, and 2) a eutectic between aluminum and BaAl4 at 98 pct Al. The accompanying sketch shows the experimental arrangement for the preparation of the alloys. Weighed amounts of aluminum and barium were placed in an alumina and a stainless steel crucible, respectively. According to the supplier's specification, the purity of the metals used in the alloys is as follows: a) aluminum rods—99.9 pct Al, and b) barium rods—99.5 pct Ba. The stainless steel crucible, tapered at the bottom and having a 1/16 in. diam hole, rested on top of the alumina crucible. The assembly was placed inside a graphite sleeve which rested on a refractory platform. The platform moved the assembly up and down through the field of a radio frequency coil. A glass bell jar was placed between the crucible assembly and the radio frequency coil to maintain a steady flow of helium around the melt. A small window was cut out on the wall of the alumina crucible to observe the progress of the re- action and to record the temperature with an optical pyrometer. The platform was first raised high enough to move the barium out of the radio frequency coil field in order to allow only the aluminum to melt. The assembly was then lowered so that the barium began to melt and flow out through the small orifice into the molten aluminum. In order to keep the violence of the exothermic reaction under control, the rate of flow of barium was carefully regulated by raising or lowering the crucible assembly. All the samples prepared by this technique were examined by a Norelco X-ray diffractometer using CuKa radiation, The diffraction specimens were prepared by placing the finely powdered samples in flat specimen holders. The Ba-Al alloys prepared with a high barium content were found to consist mainly of BaAl4. The structure of BaAl4 has previously been reported by Alberti and Andress.8 They found that BaAl4 was body-centered-tetragonal with an a0 = b0 = 4.530Å and c0 = 11.14Å. An alloy whose composition was found by chemical analysis to be almost 100 pct BaA1, was used to determine the relative intensities. The d-spacings were obtained from the same alloy to which a small amount of tungsten had been added as a calibrating material. Accurate values for a, and c, were calculated according to the method proposed by Taylor and Floyd.' The calculated values are: a, = b, = 4.566Å and c0 = 11.250Å. The measured d-values for BaAl4 are shown in Table I along with relative peak intensities above background and hkl indices. Acknowledgment The authors are grateful to L. J. Cronin, the head of the Techniques Dept., for suggesting the problem and for his constant interest. References 1Froges and Camargue: German Patent No. 809107, 1951. French Patent No. 935324, 1949. 2E. Bonnier: Annales de physique, 1953, vol. 8, pp. 259-312. 3M. Orman and E. Zemhela: Prac Institute of Metals; 1952, vol. 4, pp. 437-445. 4E. Fujita and H. Yokomizo: Reports Gov. Chemical Industrial Research Institute, Tokyo, 1952, vol. 47, pp. 291-297. 5E. Alberti: Ztsch. fur Metallkunde, 1934, vol. 26, p. 6. 6E Alberti and K. R. Andress: Ztsch. fur Metallkunde, 1935, vol. 27, p. 126. 7 A. Tnslor and R. W. Floyd: Acta Crystallographica, 1950, vol. 3, p. 285.

Jan 1, 1958

By T. A. Rickard

The function of a preposition is to show the relation of one thing to another; it is necessary therefore for the writer to select the preposition that indicates the particular relation, otherwise he will fail to express himself clearly. Is it against common sense' to suggest that a Government is justified, morally as well as constitutionally, in preventing the decay of an industry by insisting upon the amalgamation of the prosperous with the needy? All these seven prepositions are used correctly. With the first dredge introduced in Russia, of Werf Conrad, Haarlem, make, this method of alluvial dining became important. Here the prepositions "with", "in", and "of" are used wrongly. He means: "This method of a1lu;ial mining sprang into importance shortly after the first dredge, made at the Werf Conrad, Haarlem, was introduced into ;Russia." The statement itself ii not true, but for that I am not responsible. Once, while I was serving with him, we were frozen in out of sight of land in the Gulf of Pichili in the North of China. Admiral Fisher wrote thus. He has used nine prepositions in making this brief statement. The sequence of three prepositions "in out of" is particularly awkward.

Jan 1, 1931

By Alfred H. Bell

IN 1945, Illinois produced 75,210,000 bid. of oil, or 4.4 percent of the total for the United States, and ranked sixth in the nation in oil production for the third consecutive year. Production decreased about 3 per cent from that of 1944, when the total Illinois production was 77,413,000 bbl. This is the smallest percentage of decrease in production in the state for any year since a peak was reached in 1940. Daily average production for 1945 was approximately 206,000 bbl. Daily averages by months were as follows:

Jan 1, 1946

Low Zinc Prices Close Alcoa Mine Alcoa Mining Co., announced that it will suspend operations at its Hutson mine, near Salem, Ky., because of low zinc prices, January 15. The Aluminum Co. of America subsidiary announced that the low market has made zinc mining un- profitable. About 70 men were employed at the mine, with a production of about 5000 tons of zinc annually. Alcoa said the shutdown would not affect other company operations, with most of the men at Hutson absorbed in the mining firm's fluorspar operations in the same area.

Jan 2, 1953

By NEWTON B. KNOX

PERU, lying south of Ecuador and having common frontiers with Brazil, Chile, and Bolivia, includes over a thousand miles of the Andean mountains. The coastal plain is arid and narrow and the Amazonian jungle region is of interest only on account of its oil and gold placer possibilities. The mountain zone, however, here forms one of the world's most highly mineralized regions. The Peruvian Andes, like their Bolivian and Ecuadorian counterparts, form two distinct chains separated by the great Apurimac and Maralion valleys; but these rivers cut through the Eastern range to join the Amazon drainage, and the central valley is missing north of the passes thus formed by these rivers; the localities where the ranges are joined are aptly called knots. In addition, in central Peru, there exists a third range lying to the east of the first two and separated from them by the Urubamba and Huallaga Rivers. The Eastern range, however, is of little importance to the miner for few metal deposits are to be found therein except for the gold mineralization in the South. In general, deposition of metals in the Peruvian Andes accompanied igneous intrusions which invaded the folded Paleozoic and Mesozoic rocks during the Tertiary; thus the ore bodies are all typical of shallow or moderate depths.

Jan 1, 1945

By R. H. Lee

WITHOUT doubt, one of the most frequent and serious annoyances connected with the practical running of a blast-furnace, especially in single-furnace plants, is caused by low steam, in spite of the fact that all boilers at blast-furnaces have grates for burning coal, and that coal is more or less continuously burned upon them, from three to a dozen men being pretty constantly engaged around the boilers as firemen or coal- and ash-handlers. At times, when the furnace is ? tight," all available men are put on to assist the regular firemen; yet sufficient steam cannot be got to keep the engines up to their regular number of revolutions, while the stoves, deprived of the gas which has been sent to the boilers, run cold, so that, when the furnace loosens-up and resumes the regular rate of driving, the blast is very considerably below normal temperature, and a.' cold," or at best a " high-sulphur," east is the result. Again, it often happens that a furnace, running at its best, becomes temporarily a little too hot; the pressure rises; the amount of gas made' is diminished; the steam soon commences to go down; and a small scaffold is likely to form before the furnace has been brought back to the proper rate of driving, and thus enabled to take its regular amount of blast. The usual remedy is either to "jerk" the furnace by a sudden, brief intermission in blowing, or to cool the furnace by lowering the heat of the blast; but if the lower blast-temperature be maintained too long, the hearth and descending stock may be cooled below the " critical temperature " mentioned by Mr. .Johnson, and the furnace may go to the other extreme, and become cold. This is especially the case when coal or coke, high in sulphur, is used:

Jul 1, 1906

By A. W. Schlechten, R. F. Doelling

Parkes' process crusts were vacuum distilled using a shortened Pidgeon retort. Zinc was effectively removed below 800°C and recovered as a zinc sheet easily stripped from the furnace liner. Lead dasdistillationazinc required about 950°C and the resulting lead condensate tillationtended to stick to the thin metal liner. Final purity of residue is limited only by nonvolatile metals such as copper. THE successful commercial application of vacuum distillation for the removal of zinc from lead, as described by W. T. Isbell,' raises the question of whether or not a similar method can be used for other metal separations. Preliminary laboratory experiments on the vacuum distillation of Parkes' crusts by one of the authors' gave such encouraging results that it was decided to make a series of tests with large scale equipment to determine the results that might be expected in plant operation. The pilot-plant test results are reported in this paper. The great advantages of vacuum dezincing are its simplicity, the relatively low temperature of operation, and the fact that the zinc is recovered in the metallic state ready for use again in the desilveriza-tion of lead bullion. These same advantages and others would be realized from the vacuum distillation of the zinc-lead-silver crusts made in the Parkes' process. Zinc readily will distill over at temperatures of 800" to 900 °C as contrasted with the 1200°C or more used in the Faber du Faur furnace. Furthermore, the recovery of zinc as metal is practically perfect since there is no loss by oxidation or fuming. If the vacuum distillation is continued and hastened by raising the temperature to around 1000°C, the lead will distill over at an appreciable rate and deposit in a warmer zone of the condenser. This lead will contain a small amount of silver, but it can be returned to the desilverizing kettles and there is not the chance of loss that there is in disposing of the rich litharge from cupelling. The lower temperatures required will mean a saving of fuel and less wear on the equipment. One further point is that the vacuum distillation could be run on a small scale practically continuously, so as to avoid the accumulation of large amounts of silver-rich material and the need of assembling a large crew for special cupellation runs. It should be pointed out here that the final purity of the silver residue will depend on the copper or iron content of the crusts, as these and other metals with low vapor pressure will not be eliminated. The idea of treating the silver-zinc-lead crusts from the desilverization of lead bullion by vacuum distillation is not a new one, but such experiments have not been reported, as far as can be determined. In 1912, T. Turner presented a paper3 before the Institute of Metals on the vacuum distillation of brass, and a member of the audience suggested that he try his method on Parkes' crusts. In 1935, W. J. Kroll, noted for his discovery of debismuthiz-ing lead by calcium additions, published a paper' on vacuum distillation of metals and pointed out possible applications in the lead industry. Principles of Separation The successful separation of two or more metals by distillation depends upon an appreciable difference in the effective vapor pressures of the metals in the alloy to be treated. The vapor pressures of the common metals have been determined with considerable accuracy; for example, at 800°C the vapor pressures of the individual metals which are of particular interest in this paper are about .as follows: Zn, 241 mm; Pb, 0.0553 mm; and Ag, 0.0000276 mm. Unfortunately,, data are not available on the activities of the components in the ternary system Zn-Pb-Ag, but it can be estimated that on the basis of the vapor pressures of the individual metals a good separation can be made by distillation. The preliminary laboratory tests previously mentioned' supported this assumption. The pilot-plant size vacuum distilling furnace is shown in Fig. 1. It consisted of an abbreviated Pidgeon retort, 5 ft long with an ID of 8 in., heated by six silicon carbide elements placed symmetrically

Jan 1, 1952

By Eric R. Jette, Earl S. Greiner

Although the mechanical and chemical characteristics of certain iron-nickel-silicon alloys have been investigated,1 the available literature shows no results of a systematic investigation of the constitution of this system. 'This paper describes the results of an X-ray investigation of the constitution of the iron-rich iron-nickel-silicon alloys at 600°C. Data 011 the constitution of the included binary systems obtained in other investigations have been correlated with the structure of the ternary alloys. Jette and Foote2 have presented a tentative constitutional diagram of the iron-nickel system. following X-ray studies on quenched specimens. This diagram shows that the alloys at 600°C. containing from zero to approximately 4 atomic per cent nickel consist of a body-centered cubic (alpha) phase, the alloys containing 4 to 24 atomic per cent nickel consist of body-centered cubic (alpha) and face-centered cubic (gamma) phases, and the alloys containing from 24 to Ioo atomic per cent nickel consist of a face-centered cubic (gamma) phase. These investigators recognized that it was not possible to retain the gamma phase in equilibrium by quenching alloys containing less than approximately 25 atomic per cent nickel and that high-temperature X-ray methods were desirable to determine the gamma-phase solubility limit. In a later investigation of the iron-nickel alloys, Owen and Sulley3 determined the alpha-phase solid solubility limit to be 3.5 atomic per cent nickel at 600°C. High-temperature X-ray methods showed the solid solubility limit of the gamma phase to be 14 atomic per cent nickel at 600°C. Since the high-temperature X-ray method should reveal equilibrium conditions in these alloys better than the quench method of other investigators, the results of Owen and Sulley pertaining to the gamma-phase boundary are to be preferred. As the result of an X-ray investigation of quenched iron-silicon alloys, Greiner and Jette4 have shown these materials to consist of a body-centered cubic (alpha) phase containing from o to 26.4 atomic per cent silicon at 600°C. The alloys containing from 26.4 to approximately 50 atomic per cent silicon consist of two phases at 600°C.; namely, alpha and eta. The eta phase corresponds to the stoichiometrical formula FeSi (33.4 wt per cent Si)." The literature pertaining to the constitution of the nickel-silicon alloys has been reviewed by Ackerman,' who found disagreements in the results of various investigators on several parts of the system. Subsequent data on the constitution of the nickel-silicon alloys were reported by oSawa and okamoto.6

Jan 1, 1943

By Earl S. Greiner, Eric R. Jette

Although the mechanical and chemical characteristics of certain iron-nickel-silicon alloys have been investigated,1 the available literature shows no results of a systematic investigation of the constitution of this system. 'This paper describes the results of an X-ray investigation of the constitution of the iron-rich iron-nickel-silicon alloys at 600°C. Data 011 the constitution of the included binary systems obtained in other investigations have been correlated with the structure of the ternary alloys. Jette and Foote2 have presented a tentative constitutional diagram of the iron-nickel system. following X-ray studies on quenched specimens. This diagram shows that the alloys at 600°C. containing from zero to approximately 4 atomic per cent nickel consist of a body-centered cubic (alpha) phase, the alloys containing 4 to 24 atomic per cent nickel consist of body-centered cubic (alpha) and face-centered cubic (gamma) phases, and the alloys containing from 24 to Ioo atomic per cent nickel consist of a face-centered cubic (gamma) phase. These investigators recognized that it was not possible to retain the gamma phase in equilibrium by quenching alloys containing less than approximately 25 atomic per cent nickel and that high-temperature X-ray methods were desirable to determine the gamma-phase solubility limit. In a later investigation of the iron-nickel alloys, Owen and Sulley3 determined the alpha-phase solid solubility limit to be 3.5 atomic per cent nickel at 600°C. High-temperature X-ray methods showed the solid solubility limit of the gamma phase to be 14 atomic per cent nickel at 600°C. Since the high-temperature X-ray method should reveal equilibrium conditions in these alloys better than the quench method of other investigators, the results of Owen and Sulley pertaining to the gamma-phase boundary are to be preferred. As the result of an X-ray investigation of quenched iron-silicon alloys, Greiner and Jette4 have shown these materials to consist of a body-centered cubic (alpha) phase containing from o to 26.4 atomic per cent silicon at 600°C. The alloys containing from 26.4 to approximately 50 atomic per cent silicon consist of two phases at 600°C.; namely, alpha and eta. The eta phase corresponds to the stoichiometrical formula FeSi (33.4 wt per cent Si)." The literature pertaining to the constitution of the nickel-silicon alloys has been reviewed by Ackerman,' who found disagreements in the results of various investigators on several parts of the system. Subsequent data on the constitution of the nickel-silicon alloys were reported by oSawa and okamoto.6

Jan 1, 1943

By Earl S. Greiner, Eric R. Jette

ALTHOUGH the mechanical and chemical characteristics of certain iron-nickel-silicon alloys have been investigated,1 the available literature shows no results of a systematic investigation of the constitution of this system. This paper describes the results of an X-ray investigation of the constitution of the iron-rich iron-nickel-silicon alloys at 600°C. Data on the constitution of the included binary systems obtained in other investigations have been correlated with the structure of the ternary alloys. Jette and Foote2 have presented a tentative constitutional diagram of the iron-nickel system following X-ray studies on quenched specimens. This diagram shows that the alloys at 600°C. containing from zero to approximately 4 atomic per cent nickel consist of a body-centered cubic (alpha) phase, the alloys containing 4 to 24 atomic per cent nickel consist of body-centered cubic (alpha) and face- centered cubic (gamma) phases, and the alloys containing from 24 to 100 atomic per cent nickel consist of a face-centered cubic (gamma) phase. These investigators recognized that it was not possible to retain the gamma phase in equilibrium by quenching alloys containing less than approximately 25 atomic per cent nickel and that high-temperature X-ray methods were desirable to determine the gamma-phase solubility limit. In a later investigation of the iron-nickel alloys, Owen and Sulley3 determined the alpha-phase solid solubility limit to be 3.5 atomic per cent nickel at 600°C. High-temperature X-ray methods showed the solid solubility limit of the gamma phase to be 14 atomic per cent nickel at 600°C. Since the high-temperature X-ray method should reveal equilibrium conditions in these alloys better than the quench method of other investigators, the results of Owen and Sulley pertaining to the gamma-phase boundary are to be preferred. As the result of an X-ray investigation of quenched iron-silicon alloys, Greiner and Jette4 have shown these materials to consist of a body-centered cubic (alpha) phase containing from o to 26.4 atomic per cent silicon at 600°C. The alloys containing from 26.4 to approximately 50 atomic per cent silicon consist of two phases at 600°C.; namely, alpha and eta. The eta phase corresponds to the stoichiometrical formula FeSi (33.4 wt. per cent Si).* The literature pertaining to the constitution of the nickel-silicon alloys has been reviewed by Ackerman,5 who found disagreements in the results of various investigators on several parts of the system. Subsequent data on the constitution of the nickel-silicon alloys were reported by Osawa and Okamoto.6

Jan 1, 1943

By Walter E. Mingramm

THE construction of rescue-apparatus on the principle of furnishing the wearer with air from a tank containing it under high pressure was given up by inventors about 20 years ago. Such an apparatus must supply continuously, for not less than two hours, nearly 50 liters of pure air at atmospheric pressure per minute, or a total of 6,000 liters (210 cu. ft.); and a cylinder containing this amount of air, under 2,000 lb. pressure, would weigh 180 lb. or more. Although apparatus has been recently constructed utilizing liquified air, no experiments have been made to determine the regularity with which the air is generated, nor has its chemical composition been determined. Moreover, the chief objection to such an apparatus is the' difficulty and cost of keeping on hand a large quantity of liquified air. The system of furnishing the wearer of a breathing-apparatus with air which has given the best results, and has found employment in all the devices now in practical use, is that in which the air contained in the human lungs at the beginning of the work is regenerated by the apparatus. By means of chemicals, such as caustic potash and caustic soda, the carbonic acid gas, CO., exhaled is absorbed, and the oxygen that has been consumed is replaced from a tank containing this gas under high pressure. The pressure of the oxygen (which is 1,875 lb. in the two cylinders at the beginning of the work) is automatically reduced to 75 lb., and is sufficient to keep the air inside of the apparatus in constant circulation, and to force it to pass through the chemicals provided for the absorption of the CO, gas. In the attempt to construct an apparatus which would (1) furnish the wearer with a sufficient supply of air; (2) replace the amount of oxygen used up by the lungs during the time of

Jan 7, 1908

Allan Gibb, Mount Perry, Queensland, Australia (communication to the Secretary):—In drawing conclusions from his observations, Mr. Van Liew has apparently overlooked the reduction in weight that takes place in the content of the converter. The percentage-compositions of the matte, etc., are not directly comparable for determining the rate of elimination of the impurities; and, in the absence of exact weights (which in such an operation could not be obtained), it is necessary to determine the relation between the impurities and the copper with which they are combined at various stages, in order to get data that are comparable. Owing to a portion of the copper being removed in the slag, etc., the weight of copper in the converter is not a fixed quantity, but.it is sufficiently approximate to permit very reasonable comparison. The analytical data given by Mr. Van Liew, reduced to this basis (a ratio between the impurities and the copper with which they are combined), are shown in the table on page 958. From this table it will be evident that Mr. Van Liea's conclusions as to the source of heat at digerent stages are not quite correct. During the first 10 minutes, no iron is scorified, the heat being derived from the oxidation of the sulphur, of which 7 per cent. of the total is removed in this time. Prom

Jan 1, 1904

By David, Cole

THE years 1914-15-16 were a pioneering period in mining, milling, and copper metallurgy generally. It was uncertain just what path the crushing, grinding, and concentrating processes would take. This situation was quite embarrassing to the directors of some of our large porphyry properties, then being equipped for production. Inspiration had already made several designs for its proposed 15,000-ton concentrator, incorporating in them the latest devices developed in the art of gravity concentration, only to have the work vitiated by the rapid march of events. In a little improvised plant, built on ground that is now in the crater of subsidence over the Inspiration- Miami orebodies, flotation was being experimentally ' applied to Inspiration ore by Minerals Separation engineers in 1914, with results indicating that this process would be of major importance in the concentration of the sulfides. How best to apply it, and especially how to crush and grind the ore to the very much finer sizes required for the new process, was a serious question, properly to be answered only by doing it, in full- sized machines, under regular 'operating conditions.

Jan 1, 1931