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PRESIDENT WILLIAM L. SAUNDERS,1 NEW YORK, N. Y. PAST PRESIDENTS CHARLES F. RAND,1 NEW YORK, N. Y. BENJAMIN B. THAYER,3 NEW YORK, N. Y. FIRST VICE-PRESIDENT PHILIP N. MOORE,1 ST. Louis, Mo. TREASURER GEORGE C. STONE,1 NEW YORK, N. Y. SECRETARY EMERITUS ROSSITER W. RAYMOND NEW YORK, N. Y. SECRETARY BRADLEY STOUGHTON NEW YORK, N. Y.

Jan 8, 1915

By Jack L. Lytton, Oleg D. Sherby

RESULTS of recent investigations1 on the creep of metals at high temperatures have revealed that the activation energies for creep of pure metals, AH,., about equals the respective activation energies for self-diffusion, hHD. This fact strongly suggests that the rate-controlling process in creep at high temperatures might be that of dislocation climb, as first postulated by Mott.' It would be desirable, however, to relate the creep rate of a metal at a given temperature and stress with actual diffusivity data, rather than with a comparison of the tempera-

Jan 1, 1957

By Mark C. Malamphy

During colonial times, Brazil was famous for the richness of her alluvial gold deposits. Paul Ferrand has estimated that the gold produced during the period from 1700 to 1820 was the equivalent of some 64 million pounds sterling. Since that time, most of the more prolific alluvial deposits have been exhausted. A few gold mines are still functioning, notably the Morro Velho mine, which is one of the deepest mines in the world. Today, the gold production of Brazil is insignificant when compared with world figures, but there are still many gold-bearing regions and it is probable that in at least some of them profitable returns would result from an exploitation program taking advantage of all the most modern innovations in gold mining and ore treatment on a large scale. In order to demonstrate the value of some of these abandoned prospects and stir up interest in increasing the national gold production, the government has stimulated research. Experimental plants have been and are being established in various places, and tests on large quantities of ores are being carried out on a semicommercial basis. The Geological Survey of the State of Minas Geraes is very active in this line and the Federal Institution is also showing an increased interest in the matter. One of the lesser known gold-bearing regions of Brazil is in the vicinity of Lavras, in the State of Rio Grande do Sul. Gold was first reported from this region in the early part of the nineteenth century. In 1811, D. João VI sent an experienced prospector from Minas Geraes to investigate the validity of the reports. According to the reports of Baron Eschwege, he succeeded in extracting some 30,000 Oitavos (about 105 kg.) during the first few years, but the production costs exceeded the value of the gold obtained.

Jan 1, 1934

By R. F. Hewlett

All ore reserve estimates are based on some system for assigning an area of influence to each drill hole. Commonly used methods of calculation are the polygonal, triangular, statistical analysis, and cross-sectional. Each of these methods is based on different volumetric considerations and the weighting of grade with tonnage varies with each method. Because the characteristics of each mineral deposit are different, a preliminary survey of these characteristics should be made for each individual deposit to determine which method or methods should be used. In this project the several methods were not only compared with one another, but also against actual production records. Basic data was derived from a mined out portion of the Silver Bell pit near Tucson, Ariz. All calculation was carried out on a digital computer, and the first step was development of computer programs which would yield the desired information. The second step was the coding of input data into punched card form. Cost and speed of computer operation were measured, and these results are given with the computer program summaries on page 38.

Jan 1, 1961

By L. C. Campbell

THE purpose of any accident-prevention program is the curtailment or entire elimination of injuries and fatalities. It is a job that is never finished in the coal-mining industry. Day by day, on shift and off shift, men are exposed to injury and death in varying numbers. Seldom is it possible to lock up at the end of the shift and leave a mine plant in the care of a sleepy watchman, as can be done at most manufacturing plants. Even on off shifts there are maintenance and supply crews, coal cutters, pumpers and ventilation men exposed to danger. The prevention program of The Koppers Coal Co. recognizes two primary facts: First, no program can be successful without the full support of the management and complete knowledge of the job at hand on the part of every supervisor. Second, and equally important, is the full cooperation of every employee in observing the safety rules and practices set up by the management. Conscious day-to-day concern for his safety by the indi-vidual worker is the longest stride toward a good safety experience. How to accomplish the education of the individual worker and super-visor for safety is the problem of The Koppers Coal Co. as it is the problem of all coal companies.

Jan 1, 1939

By Richard Ely

Conservation Means Preservation, Improvement, Justice CONSERVATION, narrowly and strictly considered, means the preservation in unimpaired efficiency of the resources of the earth; or in a condition so nearly unimpaired as the nature of the case, or wise exhaustion, admits. And broadly considered, it means more than the word itself implies, for it naturally includes an examination of methods whereby the natural inheritance of the human race. may he improved; and still more broadly considered-and as used in popular discussion-it includes a treatment of the effects of productive conservation measures upon distribution. We shall give our attention briefly to the main points in this informal definition before we pass on to the thesis that conservation is largely a matter of property relations-that a wise conservation policy means wise property relations. Preservation of Natural Resources First, conservation suggests simply preservation, and, in the treatment of the subject which we have had in the United States, emphasis has been laid upon the past and present waste of natural resources and upon the means of putting a stop to this waste. The forests have been depleted; soil has been washed by rapidly flowing surface water from mountain sides. These rapidly flowing waters have produced high streams and devastating inundations, followed by low streams and impeded navigation. The forests have, moreover, been so removed as to bring great danger of fire, and destructive conflagrations have resulted in large waste of resources, including in some cases a destruction of the humus, supplying essential elements in the fertile soil. As a remedy we must have measures to reforest mountain sides, and this means large social control, very frequently taking the form of public ownership and management; but in addition we always find actual and proposed

Jan 2, 1916

By Frederic Carter

THE gold, silver, copper alloys have been the subject of several fairly complete investigations by Jänecke, Sterner-Rainer1 and others, and indeed it would seem as if almost too much labor had been expended on them when one thinks of the numerous other ternary alloys calling for more light; however, the combinations of the three metals are actually so widely used in jewelry that they merit perhaps the work done on them. There are a few properties of importance and interest not treated by the authors mentioned which the writer investigated some little time ago, and therefore he has ventured to put on record the results of some of his tests made at that time. He has chosen, as being the two series of most importance to the jeweler, only the 14 and 18-kt. golds, so the subject is by no means so inclusive as that previously treated. As stated, this paper is merely a record of tests made in a practical manner on two useful series of alloys, and is not at all a critical study of their properties. 14-KARAT ALLOYS These alloys are important because they are the most generally used in 14-kt. jewelry; by changing the proportions of silver and copper there are obtained all shades of color from the green of the alloy containing gold and silver but no copper, to the red of the alloy containing gold and copper but no silver. Many 14-kt. gold alloys are made with the addition of zinc to the three metals mentioned here; the added metal does not appreciably alter the color of the alloy nor has it, in general, much effect on the working properties; it may, however, prove useful as part of the zinc added may act as a deoxidizer and render the alloy free of gas. It is not a necessary addition because with proper precautions all the 14-kt. gold alloys containing only silver and copper in addition to the gold can be made free of gas and capable of being cold rolled without cracking. The alloys in which approximately equal quantities of silver and-copper

Jan 1, 1928

By Alden B. Greninger

THE time-honored description of the growth of metal crystals to form polycrystalline aggregates is. one in which two important steps are considered: (1) nucleation, and (2) dendritic growth, each dendrite starting from its individual nucleus and resulting (upon slow cooling, assuming no solid phase changes) in a macrograin. This picture of the process of crystallization is incomplete, and it is with the hope of enlarging upon it that the following summary and correlation of experimental results are given. MOSAIC STRUCTURE For an exact definition of the mosaic structure of metal crystals-if, indeed, one can be found that will hold for all metals-one must await the results of much experimental work in this field. The writer's investigations have been. confined almost entirely to copper and a few of its alloys. The following terms are proposed, and will be used in this report: Macromosaic Structure1.-Large-scale mosaic structure; more specifically, mosaic structure of a scale large enough to produce splitting of Laue spots on back-reflection Lane X-ray patterns2. The deviation from exact parallelism of neighboring macromosaics varies from a few

Jan 1, 1935

By Hiroshi Oikawa, R. G. Blake, A. G. Guy

An equatzon has been derivedfor conveniently calculatzng the couvse of homogenzzation in a three-corviDonent solid solutiorz. The necessary assumptions are that the initial distributions of concentration are sinusoidal and that the four interdiffusion coefficients are constant. Employed in the deriuation were the Laplace transform and the fouter Fourier sine transfovwz. The final equation is shown to be in good agveetnent with the experimental results of Kirkaldyet al. on Cu-Sn-Zn alloys. COMMON boundary conditions for representing physical problems are those of the finite solid and of the infinite solid. Many metallurgical phenomena, however, have the geometrical form of a finite pattern reproduced throughout an infinite solid. Precipitation within a uniform matrix and segregation during solidification are examples. The purpose of this treatment is to show that a convenient and useful mathematical analysis is possible in those cases in which the finite pattern can be approximated by a sine function. The particular topic to be considered here is the elimination of segregation by diffusion, but the mathematical model has applicability in many other areas. It should be recalled that the mathematical solution of a typical problem involving a finite solid, such as diffusion into a thin layer, is quite involved.' Various types of solutions are used depending on the degree of advancement of the diffusion process and on the initial conditions. A step function is the simplest initial condition, but even in this case the general solution has the form of an infinite series. Kirkaldy et a1.2 have

Jan 1, 1968

Discussion of the paper of J. V. EMMONS, presented at the Pittsburgh meeting, October, 1914. and printed in Bulletin No. 93, September, 1914, pp. 2233 to 2248. ALBERT SAUVEUR, Cambridge, Mass.-Mr. Emmons is to be congratulated for having placed before us in so forcible and satisfactory a manner a question of much importance-that of the surface decarbonization of steel. Of course, both manufacturers and consumers have known for many years that during the heat treatment of high-carbon steel, surface deca.rbonization is always likely to occur to a greater or less degree, but the subject does not seem to have been investigated with the method and thoroughness it deserves. I am in substantial agreement with Mr. Emmons's conclusions, and I have but little to add to what he has so well said. His statement that carbon dioxide is just as effective an oxidizing agent as pure oxygen is likely to cause surprise and some will wonder whether his investigation has been carried far enough to warrant so unexpected a conclusion. The reaction C + 0 = CO, expressing the oxidation of carbon by pure oxygen, is decidedly exothermic, whereas the reaction C + C02 = 2C0, expressing the oxidation of carbon by carbon dioxide, is endothermic. Decarburization by pure oxygen, therefore, should take place much more readily than by carbon dioxide. One cannot help regretting that the author does not mention' the best way of preventing in a practical manner surface decarbonization while treating tool steel and other high-carbon steels.

Jan 4, 1915

By S. Yukawa, M. J. Sinnott

A high resolution autoradiographic study of the diffusion of a nickel isotope (NP3) into copper in the temperature range of 650° to 925°C, with particular emphasis on grain boundary diffusion, has been made. The extent of grain boundary diffusion is a function of the grain boundary angle and the diffusion temperature. The ratios of the grain boundary diffusion coefficient to the lattice diffusion coefficient ranges from 104 to 105. The activation energy for grain boundary diffusion decreases with increasing grain boundary angle. STUDIES and reviews&apos;-8 of metallic diffusion have indicated that grain boundary diffusion is a common phenomenon but quantitative studies of the many variables involved are not numerous. The present work was concerned with determining the influence of the crystallographic orientation of the grain boundaries and the temperature on the extent of boundary diffusion of nickel into copper. The study involved essentially three steps: 1—the production of grain boundaries of known crystallographic orientation, 2—the determination of the extent of diffusion into the boundaries, and 3—the analysis of the resulting data in terms of the usual diffusion concepts. The grain boundaries investigated approximated the simple tilt variety having l° of freedom. They were produced by controlling the solidification from a melt of Cuprovac (a high purity vacuum-melted copper obtained from Vacuum Metals Corp.) of a pair of seed crystals so that the bicrystals of copper produced had a common <100> axis. By rotating one seed crystal relative to the other, a simple tilt boundary was produced. The angle of rotation between the two crystals is the grain boundary angle 8, or what is sometimes termed the misfit angle. In all, some 16 boundaries ranging from 2" to 72" in 5" to 10" steps were investigated. The crystallographic orientations were measured with the use of both X-ray and optical goniometric techniques. The <100> axes in the crystals were found to be parallel within 2" to 3" with the exception of one crystal (8 = 12") in which the axes were 6" from being parallel. All bicrystals showed evidences of sub-grain structures. Laue analyses showed that these subgrains differed in orientation up to a maximum of 2". Because of these variations, and some curvature in the boundaries, the grain boundary angles listed are actually average values and deviate from the 1 o of freedom boundaries. The stripping film technique of high resolution autoradiography was used to detect the diffusion of the nickel isotope into the grain boundaries of the bicrystals of copper. Kodak experimental permeable stripping film with an emulsion layer 5 u thick

Jan 1, 1956

By W. P. Blake

The mining district and the town of Tombstone are situated in Cochise County, Arizona Territory, at the northwest end of the Mule Pass range of mountains, in longitude 110°, and latitude about 31 40&apos; N,, upon the right bank of the San Pedro River, from which the town is distant 9 miles east.. It is also 24 miles south of Benson station on the Southern Pacific Railroad of Arizona, and about 40 miles north of the Mexican line. Its altitude above the sen is 4600 feet. The Dragoon Mountains rise across a valley to the northeast, and the Huachuca Range similarly upon the southwest. The country is open, without timber, and the surface, where the mines are opened, is in general gently rolling, and accessible to wagons by. natural roads. The first locations were made in the pear 1878 by the Scheffelin brothers and Richard Gird, the latter being well known among the pioneers of Arizona as a surveyor and miner, who contributed largely to our knowledge of the geography of the Territory in early days,

Jan 1, 1882

By L. R. Testardi, J. R. Wiese

OBSERVATIONS have been made that the substitution of antimony for bismuth in Bi2Te3 leads to anomalies in some of the electrical and magnetic properties of the Bi2Te3-5S2TeS alloy system at the composition ratios 2 Bi2Te3 : 1 Sb2Tes and 1 Bi2Te3 : 2 Sb2Te3. Airapetiants and Efimova1 have reported the peaking of the nondegenerate hole mobilities, at these compositions for sintered materials and ascribe the peaking to the formation of ordered alloys. From a study of these materials produced by the Bridgeman

Jan 1, 1962

Such are the rigors of climate and topography of western Tasmania, that much of the area has remained uninhabited. The mountains, rising to peaks above 5000 ft high, receive the winds out of the west and precipitate 110 in. of rainfall a year on this coast. The drenched forests have a primordial look with such unfamiliar trees as the tru-sassafras, blackwood, cheesewood, ti tree, and man tree ferns. Prospectors speak of the "horizontals," trees which, in the dense foliage, grow out flat. When the explorer climbs over them he does not come back to the ground but continues forward on dense vegetation with the ground many feet below. Gold was discovered by the intrepid prospectors of the late nineteenth century and stamp mills were erected in the vicinity of Zeehan and Queenstown. At Mount Lyell, mining began for gold in the ironstone capping. The familiar story, of course, is that copper was found beneath the gossan and it was this mineralization that lead to permanent mining operations. Two companies began mining at Mount Lyell and their history from 1893 to 1902 was marked by an unreasonable competitiveness, human perversity and technical difficulties. The North Lyell and Mount Lyell companies were mining copper ores within one mile of each other separated only by a ridge. Each company built its own railroad and harbor. For six years of struggle both companies tried to work out the metallurgical problem which was the key to profit. Although they didn&apos;t know it, the two ores were complimentary and could have been smelted together. North Lyell ore was strong in silica and weak in iron, whereas Mount Lyell was fortunate in having a first-class metallurgist in Robert Sticht, from Brooklyn, N. Y., who in 1902 successfully achieved pyritic smelting without the use of carbon fuel.

Jan 10, 1964

By F. C. Langenberg

DURING the course of some magnetic investigations which the authors have under way, six bars of 0.43-carbon steel were tested, a permeameter designed after the Hopkinson yoke type being used. The results obtained were of some interest and although far from complete serve at least to show the necessity for a careful investigation of the previous history of the samples under study as well as the chemical composition. A steel of given chemical composition may assume a great variety of structures, depending on its treatment. Professor Sauveur has devised a very clear and effective means of illustrating this point: The accompanying microphotographs show some of the possible structures assumed by a 0.30 carbon steel (Fig. 1). It is now a well-established fact that a structural change is accompanied by changes in the tensile strength, elastic limit, hardness, etc., and it seems reasonable to assume also, a change in the magnetic properties. Six bars of a 0.43-carbon steel were used, all the bars being taken from the same rod and treated as follows: Bar 1. Heated to 1,100° and cooled in the furnace. Bar 2. Heated to 1,000° and cooled in the furnace. Bar 3. Heated to 900° and cooled in the furnace. Bar 4. Heated to 1,000° and cooled in air. Bar 5. Heated to 900° and cooled in air. Bar 6. Untreated. The bars were then turned to 13 mm. diameter and tested by the Hopkinson yoke method. After testing, three specimens were taken from each bar, one from each end and one from the middle. The homogeneity of the. bars was tested in this manner and in no instance could any difference in structure be detected between the three specimens.1

Jan 2, 1915

THE CHAIRMAN (A. F. Lucas, Washington, D. C.).-Mr. Matteson has stated that the drilling of certain deep wells has proved a failure because they were abandoned too soon. He advises drilling more wells around salt domes, in the hope of finding additional oil sands. I have had some experience on the domes and believe that by drilling shallow wells, one loses time and money. I have advanced the opinion -that by drilling central wells in the -most likely location of a dome, showing is certain weakness, a better result could be obtained. I have in mind one locality where Mr. Knapp drilled a well through the salt¬the only location that I know of on the Gulf Coast where oil was found underneath the salt. Mr. Knapp found a great deal of gas in it. The salt itself was impregnated with oil and gas; and my opinion is that in such instances, instead of drilling so many wells around a dome, if you will attack at a weak point to as great a depth as a drill will go, the results will he much better. At present we have instances where drills have penetrated to 7300 or 7400 ft. in depth. Why couldn&apos;t the rich companies that are operating around the Gulf Coast arrange to get some special drilling apparatus and drill with the rotary first for, say, 3000 to 4000 ft., always in the likely location, and then proceed with the cable? I think we need just such work. In Mr. Matteson&apos;s paper lie quotes from an author whose writings in the Federal Bulletin and in the Louisiana Bulletins have been quite extensive. He states that oil and asphalt have originally been found on the surface of those domes. I have been over and examined nearly all of those domes (not all of them, because many have been developed in the last few years) and found no such occurrence at the time; and in the old well-known humps or big hills, as they generally called them; I have never found either salines or asphalt or petroleum. In only&apos; one instance it looked as though asphalt night have exuded out of the ground, and that was in the Sour Lake, but right in that neighborhood years previous to that a company had operated commercially-they had a little refinery there-and had found it so unprofitable that they pulled up stakes and quit.

Jan 4, 1918

FIRE tubes are commonly made in order to frighten horses or to harm enemy soldiers, but although fire issues from them, they do not cause much damage because they cannot be used at a distance. If you wish to use them, you are not able to approach close to the enemy, for if there is anyone who is afraid, he does not let you approach nor does he come near you until he sees that they have finished burning. Thus, in short, the assault with this is one that is seen beforehand, and for which there is always time to decide on some action in defense. It is indeed true that they are beautiful things to see and when the name tubes of fire is heard it terrifies those who do not have a defense ready. When four, six, or indeed ten or twelve of these are put in the hands of as many courageous and united men, they are surely good in forcing passage on a guarded bridge, or in entering or holding a gate, road, or other narrow place. They serve also for setting fire to dwellings or the enemy&apos;s supplies,

Jan 1, 1942

By M. T. Halbouty

The Laredo oil district, South Texas, includes an area of approximately 200 miles long north and south and 75 miles wide, embracing the following counties: Starr, Zapata, Jim Hogg, Webb, Duval and McMullen. The area is relatively old in respect to the production of oil, as the first oil was discovered and produced in the Piedra Pintas field in Duval County on Sept. 10, 1905. Since that date, continuous new discoveries have contributed to the development of this district until, at the present time, it is one of the important oil-producing and gas-producing areas in the world. The year 1937 also had its share of new discoveries in the district, including not only new oil fields but also new sands in already producing pools and important extensions to existing sands and fields. Among the most important field discoveries, by counties, are: Duval County..... Benavides, Sweden, Thomas-Lockhart, Labbe and Lundell fields Jim Hogg County.. Las Animas field McMullen County. Ezzell field Starr County...... El Tanque field Webb County..... Killam and Oilton fields Of these, Benavides, Oilton, Killam and Ezzell have so far proved themselves most important; the Benavides field, Duval County, showing by far the most activity. For the year 1937, therc were 283 wildcat tests drilled in this district, of which 35 were oil producers, 20 completed as gas wells and 228 abandoned as dry holes. Duval County, as usual, received the greatest amount of wildcat drilling, having 21 oil wells, 5 gas wells and 63 dry holes completed during the year for a total of 89 tests. Next came Webb County with 4 oil wells, 4 gas wells and 53 dry holes for a total of 61 tests.The Laredo oil district, South Texas, includes an area of approximately 200 miles long north and south and 75 miles wide, embracing the following counties: Starr, Zapata, Jim Hogg, Webb, Duval and McMullen. The area is relatively old in respect to the production of oil, as the first oil was discovered and produced in the Piedra Pintas field in Duval County on Sept. 10, 1905. Since that date, continuous new discoveries have contributed to the development of this district until, at the present time, it is one of the important oil-producing and gas-producing areas in the world. The year 1937 also had its share of new discoveries in the district, including not only new oil fields but also new sands in already producing pools and important extensions to existing sands and fields. Among the most important field discoveries, by counties, are: Duval County..... Benavides, Sweden, Thomas-Lockhart, Labbe and Lundell fields Jim Hogg County.. Las Animas field McMullen County. Ezzell field Starr County...... El Tanque field Webb County..... Killam and Oilton fields Of these, Benavides, Oilton, Killam and Ezzell have so far proved themselves most important; the Benavides field, Duval County, showing by far the most activity. For the year 1937, therc were 283 wildcat tests drilled in this district, of which 35 were oil producers, 20 completed as gas wells and 228 abandoned as dry holes. Duval County, as usual, received the greatest amount of wildcat drilling, having 21 oil wells, 5 gas wells and 63 dry holes completed during the year for a total of 89 tests. Next came Webb County with 4 oil wells, 4 gas wells and 53 dry holes for a total of 61 tests.

Jan 1, 1938

By Julian Kennedy

The different types of blowing-engines in use are so numerous that it would not he practicable to consider them all in this paper. I shall therefore only take up briefly a few well known types. The style of blowing-engine most largely used in this country is the vertical engine with air-cylinder above, cross-head between steam and air-cylinders, and two fly-wheels, each having a wrist-pin in its hub, or in one arm. This kind of engine can be built cheaply, takes up little room and is very accessible. Its disadvantages are that the cross-head is liable to break, and that putting the wrist-pins in the wheels tends to set up vibrations in them. It is likely that on the whole this type of engine will continue to be built quite ex tensively. The same general arrangement has also been used to some extent, but not widely, in horizontal engines. The Bethlehem Iron Company has some very fine blowing-engines of this type, except that they are compound, having the one steam-cylinder replaced by two, side by side. These engines are noticeable not only for the very excellent workmanship on them, but also on account of the weight of the pistons being carried by steam-pressnre applied in chambers in the lower side, the steam being supplied to these chambers through the hollow piston-rods. This arrangement, I believe, has always worked well. Another type of engine which has given good satisfaction is the vertical double-engine, having air-cylinders above, steam-cylinders below them, and cranks at bottom, the engines being coupled to cranks on the ends of the shaft, placed at right angles to each other, the shaft carrying the fly-wheel at its center. Engines of this type, except that they are arranged horizontally, are also used to a con siderable extent. These engines avoid the disadvantage of having wrist-pins in the fly-wheels, and also dispense with the long cross head with its attendant disadvantages. They give a very uniform pressure of blast, and are very convenient for starting. The vertical engines of this type, as compared with the horizontal, take up less

Jan 1, 1894

By Carl E. Swartz

In the course of a recent investigation1 to develop a more satisfactory white-metal bearing alloy, a number of alloy systems were studied. The cadmium-nickel system showed characteristics desirable in a bearing alloy, and the system was therefore studied in some detail. Experimental Method Alloying cadmium with nickel offered no serious difficulty. After melting the cadmium, clean sheet nickel was added while the temperature was maintained at 500" to 600" C. A few crystals of ammonium chloride2 served to clean the nickel when the latter did not "wet" readily. In preparing the individual alloys for thermal and microscopic investigation, a "hardener" containing about 10 per cent nickel was used. Thermal Experiments and Apparatus Time-temperature cooling curves were made by standard methods. Globe electrolytic cadmium was added to the hardener to make a melt of the desired composition weighing between 100 and 200 grams. This charge was placed in a Pyrex test tube, 1 by 10 in., closed with a rubber stopper carrying a thermocouple sheath and quartz stirring rod. The assembly was lowered to a depth of about 4½ in. into an electric resistance pot furnace containing a No. 0000 clay-graphite crucible (to catch the melt in case of a break in the test tube). After the tube was clamped in this position, an asbestos-magnesia mixture was loosely packed in the furnace around the tube and a "halved" cover of transite placed on top. This left at least 5 in. of the test tube protruding from the furnace. When the alloy had melted, the thermocouple was adjusted so that the hot junction was l! in. from the bottom of the test tube. The melt was stirred thoroughly for several minutes to insure composition homogeneity and absence of thermal gradients.

Jan 1, 1934