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By Miguel Bustamente

In 1890 I mas manager of a mining enterprise in the State of Michoacan. The ores were composed principally of iron pyrites (much decomposed), in a quartz matrix, with native gold in very irregular grains. Some portions, however, carried their metallic value in a matrix of calcite arid siderite. The mill in which the ores were treated consisted of two 800-lb. stamps, two amalgamating-plates, four pans, two automatic washers, two Frue vanners, and the necessary accessories for assaying, retorting and refining gold. The plant, originally erected with American capital, and directed by competent Americans, passed in 1890 into the hands of Mexican owners. On taking charge of the business I found on hand a large amount of ore assaying 35 grammes of gold per metric ton (about 1 oz. Troy per ton of 2000 lbs.); but the company was losing money, and was about to abandon the business. Obviously, the difficulty lay in the treatment of the ore. The extraction of gold scarcely reached one-tenth of the assayvalue ; the loss of mercury was considerable; and high freight; charges excluded the alternative of exporting the ores. This situation naturally suggested that amalgamation was not applicable to these ores, and that a more appropriate method must be adopted. The cyanide- and chlorination-methods had been tried already, without practically satisfactory results. For the first few months I employed a combined system, extracting a part of the gold by direct amalgamation, and cyaniding the concentrates. This saved 32 per cent. of the assay-value, but the cost of milling still exceeded the proceeds. Meanwhile I observed

Jan 1, 1902

By Spencer Cragoe

I have read with much interest the elaborate and able paper of Messrs. Granger and Treville on the Mining Districts of Colombia, presented at the Atlantic City Meeting (ante, p. 33). Going into detail, however, as the paper does—and particularly with reference to the department of Antioquia, I am somewhat surprised that the property of the Frontino and Bolivia Company, probably one of the richest and most extensive in Colombia, should come off with such scant notice. The entire property embraces an area of some 28 square miles, and is situated at a distance of about 2 leagues from Remedios—after Medellin probably the most important town of the Department—and lying in approximately '7° N. latitude. The neighborhood of Remedios has been long celebrated for its production of the precious metal. Alluvial gold in large quantities has been obtained from the vicinity for upwards of two centuries; and even to-day a large proportion of the population finds a comfortable livelihood, during the dry season, in washing the sands of various rivers, notably the Rio Porce; while the amount of gold, in the form of nuggets, brought almost daily to Remedios and other points, from streams in the immediate neighborhood, is astonishing. These nuggets vary much in size. The majority, of course, are small, but larger ones are by no means scarce. I have been considerably surprised at the amount and value of the trade thus transacted between natives and merchants of the various towns. The property owned by the Frontino and Bolivia Company has been, I believe, for the larger part of the present century,

Jan 1, 1899

By Charles McElroy White

IT is indeed an honor to have been asked to participate in the program which celebrates the seventy-fifth birthday of the American Institute of Mining and Metallurgical Engineers. This great organization has occupied an important place in the professional and industrial life of this country-of the world. Its members have explored the far reaches of our globe and have played a great part in the discovery, extraction and utilization of the mineral resources upon which our civilization so largely depends. These engineers, together with the restless prospectors, on the one hand, and the scientists, on the other, have literally been the advance scouts of our modern way of life. As such, we owe them a deep and lasting debt of gratitude. May I, therefore, wish many happy returns to the American Institute of Mining and Metallurgical Engineers and express the hope that it may long continue to be of great service, as it has been in the past. The subject assigned to me-Iron Ore and the Steel Industry-is, indeed, important, as one considers the future of our world. I shall give as few figures as possible. Pertinent statistical data are included in the tables in this chapter, which, I think, will prove interesting. Many studies of iron-ore reserves have been -published and are available; hence I shall limit myself mainly to an interpretation of these figures. The statistics data are from standard sources, including the Lake Superior Iron Ore Association, the American Iron and Steel Institute, the United States Bureau of Mines, the United States Geological Survey, the United

Jan 1, 1947

F. J. DE WILDE, Galena, Ill. (written discussion *) .-As it is impossible to spare the time for a lengthy discusson of this excellent paper, I am dwelling only on points where either the information is not clear or opinion differs radically from that of the authors. On page 1218, relative to oil rock, the authors state that the presence of oil rock is always taken as a favorable indication of proximity to ore. As thick, highly carbonaceous, oil rock has been found quite often in isolated patches outside of the district proper, the mere presence of oil rock is not always an indication of the propinquity to ore deposits. Regarding glass rock, I agree with the authors, that, generally speak-ing, sphalerite in the glass rock is spotty; however, they fail to mention that nearly all mines contain more or less ore in the glass rock, the usual location being near the toe of the pitch. On page 1220, they say that disseminated deposits are only found in, or close to, the oil rock. To refute this statement, I refer them to a typical disseminated deposit situated at the Adam and Eve shaft of the Frontier Mining Co. This deposit is located in the central horizon of the Galena dolomite, that is, in those sedimentaries containing flint nodules. Perfect crystals of sphalerite are found disseminated through-out the rock, and are commonly known by the miners as strawberry jack. I believe all top runs, or upper deposits as described above, should be classed as disseminated; physically the ore makes its occurrence in just such a manner.

Jan 11, 1919

By David Baker

IN a paper presented to the American Institute of Mining Engineers, September, 1904, entitled ? Improvements in the Mechanical Charging of the Modern Blast-Furnace,"' I showed the great fault of mechanical charging-devices to be that the materials charged by the dumping of the skip were separated, the coarse materials having high velocity, and the fine, low-thus giving paths of low resistance through the stock in the furnace, which resulted in unequal distribution of the furnace gases, unequal reduction, slips, scaffolds, irregular cutting of the. inwall, " off " iron, and increased fuel-consumption. I showed how this could be prevented by rotary distribution, through which the irregular distribution in one layer charged is compensated by charging the subsequent layers from successively varied positions of the charger, and becomes practically eliminated when the angle between two successive positions is a little more or less than an even fraction of a full circle. Of all the devices then on the market, the nearest approach to the ideal arrangement was found in the Brown distributor, a full description of which was given. The one defect pointed out, however, was the difficulty of maintaining so much mechanism on the top of a blast-furnace. Since the presentation of that paper, I have designed a very simple form of rotary distributor, which may be applied to any form of double-bell charger, retaining the perfect gas-seal, which is so admirably obtained by that construction. In seeking protection for this invention, I found no similar distributor on record in the patent offices of the various countries where application was made; but an application show-

Jul 1, 1906

AS I told you before in the treatise on ores, once these are found (whether they are ores of metals or semiminerals) it is necessary to assay them in order to know what is in them, since the judgment of the sight is not sufficient for recognizing the quantity or even what substance they contain. For this reason, it is necessary to come to assaying and, with the knowledge of experience, to weigh their virtues and to proceed with the work or withdraw from it and its expense; and also through knowledge to make provision for their defects if some evilness harms the ores. For if you should have need of a thing that would help them and should not find it, all that you have done would be lost; and, on the other hand, if you should find that the ores are abundant and rich and easy to smelt, you take courage to continue without respect for anything. Therefore, in the following book I shall tell you first in general how the assay of all the metals should be made. I shall enlarge in particular on silver more than on any of the others since it is more important. Then I shall tell you how the ores should be prepared for smelting and also how blast furnaces and other furnaces for smelting such ores should be constructed, and finally how all elemental mixtures of metals are to be separated one from the other with the ability and power of art, and how they are reduced to their final perfection and fineness according to their species.

Jan 1, 1942

By Charles A. Colton

(Read at the Amenia Meeting, October, 1877.) THE results of a series of analyses extending over a period of three weeks at the Cedar Point Iron Company's furnace, Port Henry, New York, are given in Tables I and II. This furnace uses a very pure magnetite and Lehigh and Lackawanna anthracite. The flue leading the gas from the "down-comer" to the boilers was tapped by a a inch gas pipe, which carried the gas to the Orsat apparatus. The pressure of the gas not always being sufficient, owing to the small amount made, to force it into the apparatus, I omitted taking samples several days, and with the exception of the last three days of the campaign, made the analyses whenever opportunity offered. I find the Orsat apparatus, as described by Prof. Egleston,* to work very well, with one exception. The CO is not absorbed as readily in the ammonia-copper solution as he states in his description of the apparatus, as many as 50, and sometimes 60, passes being necessary to absorb all the CO. The power of absorbing rapidly increases as the solution is used, and this would indicate that the more oxygen it contains the quicker will it do the work. Probably the addition of a small amount of some oxidizing agent would remedy this. When the furnace was working in its normal condition, I had no occasion for using the filter, the amount of fume being so small as not to cause any inconvenience. The gas burned with the flame peculiar to CO, and contained just enough solid particles to give it a slight reddish tinge. * See Transactions, II, 226; V, 487, 621.

Jan 1, 1878

E. T. DUMBLE, Houston, Tex.-This paper is a continuation of one that was published by Mr. Garfias, I believe, in the Journal of Geology, 1912, in which he gave the results of his investigations in Mexico, showing that the basalt extrusions frequently did not come up as cones. but reached the surface as a small neck and then mushroomed out into a sill, penetrating the beds both in limestones and in shales. He has continued his investigations to show that as these basalt protrusions came up they forced the strata into a funnel shape at the top instead of throwing them out altogether. While this may be true concerning these particular beds, there are other places at which the basalt does appear clearly as cones and dories, and there the funnel structure does not exist. We know that the sills are there, because we find them in the wells. In one well that I know of. we found a 2-ft. sill of basalt at about 1600 ft. and oil below it at about 2100 ft.; others have gone through similar beds. We also know that there. are cones, because north of the Ranuco River one well struck basalt at about 800 ft. and continued in it for several hundred feet-did not pass through it at all. This paper of Mr. Garfias will give us considerable help in that oil field. W. E. WRATHER, Wichita Falls, Tex.-I would like to ask for information as to the temperatures of Mexican oils. I have heard a number of conflicting reports about the high temperatures of the water and oil, and the relationship between them.

Jan 1, 1918

By Charles A. Colton

The results of a series of analyses extending over a period of three weeks at the Cedar Point Iron Company's furnace, Port Henry, New York, are given in Tables I and 11. This furnace uses a very pure magnetite and Lehigh and Lackawanna anthracite. The flue leading the gas from the "down-comer" to the boilers was tapped by a 2 inch gas pipe, which carried the gas to the Orsat apparatus. The pressure of the gas not always being sufficient, owing to the small amount made, to force it into the apparatus, I omitted taking samples several days, and with the exception of the last three days of the campaign, made the analyses whenever opportunity offered. I find the Orsat apparatus, as described by Prof. Egleston," to work very well, with one exception. The CO is not absorbed as readily in the ammonia-copper solutiou as he states in his description of the apparatus, as many as 50, and sometimes GO, passes being necessary to absorb all the CO. The power of absorbing rapidly increases as the solution is used, and this would indicate that the more oxygen it contains the quicker will it do the work. Probably the addition of a small amount of some oxidizing agent would remedy this. When the furnace was working in its normal condition, I had no occasion for using the filter, the amount of fume being so small as not to canse any inconvenience. The gas burned with the flame peculiar to CO, and contained just enough solid particles to give it a slight reddish tinge.

Jan 1, 1879

M. G. CORSON.'-I am not going to discuss any of the papers presented but merely the question of season cracking of brass in general. Alpha brass has been known for nearly 500 yr. and from the very beginning a number of articles were made from sheets of this alloy by the process of spinning. Metal turning lathes were not yet known but wood turning lathes already existed and the wood turners used to make the mandrils and do the brass spinning themselves. Cases of season cracking were known even then. In 1915 I was connected with a small company doing a certain amount of brass spinning. Before the war its products never gave cause for complaint but their war-time products were cracking too frequently. The reason was, that due to the exigencies of war an excessive speed-up was attempted and the material simply could not take it. Today corrosion cracking of brass is most important in the case of cartridges for small arms ammunition and shell cases for large guns. The cracking takes place in storage and too frequently it is explained by the hypothetical presence of vapors of ammonia. However, I had the experience of purchasing some 20,000 rounds for the old Vetterli rifle from the Swiss government in 1905. The rifle and the cartridges were obsolete for many years and those which I bought were stored for at least 10 yr. None of them was found to be cracked or to crack in use. And the reason again was in the amount of work used in manufacturing the cartridges between anneals. The machinery today is more powerful and the amount of

Jan 1, 1945

By Y. C. Liu, G. A. Alers

measurements of the anisotropy in Young's modulus produced in copper by rolling 95 pct reduction in thickness below room temperature have been carried out in order to study the dependence of the texture on rolling temperature. The results clearly show the transition from a copper-type texture to a brass-type texture as the temperature of rolling is lowered. The intermediate textures observed can be described very well as a simple mixture of the two terminal textures. These results cormbined with other texture measurements make possible afresh review of the experimental facts velating to rolling textures in fee metals and, as a consequence, a critical examination of the current theories is presented. PREVIOUS experiments have shown that the transition from the copper- to the brass-type rolling texture is clearly displayed and can be quantitatively analyzed by measurements of the anisotropy of Young's modulus.' Application of this method to the Cu-Zn alloy system showed that the description of the texture transition as a gradual rotation of the grains from the orientation characteristic of the copper texture to the {110}(112) texture of brass2 was inconsistent with the data. Instead, the data suggested that the texture within the transition region could be described as a simple mixture of the two terminal textures.5 Unfortunately, it was difficult to establish this point conclusively because of the inadequacy of corrections for the composition dependence of the single-crystal elastic constants. Since a rigorous establishment of the nature of this texture transition is essential to our understanding of the formation of rolling textures in fee metals, it is clearly important to undertake an investigation in which the composition dependence of the elastic constants would not enter. A suitable composition-independent texture transition is provided by the well-established variation in the rolling texture of copper with rolling temperature. This temperature-dependent texture transformation has been studied by smallman' in several fee alloys and by Müller5 and others"' in copper. They observed that the texture characteristic of copper rolled at room temperature changed to a brass-type texture when the rolling temperature was lowered to 77°K. Although it is not possible to decide unequivocally from the published pole figures whether or not the 77°K rolling texture of copper is entirely of the brass type,' this complication does not affect the main purpose of the present investigation. In addition to establishing the nature of the texture within the transition region, the modulus data should also provide a determination of the temperature at which the transition occurs as well as the temperature range over which the transition extends. This information when combined with the modulus data on Cu-Zn alloys would then provide a considerable body of new information on textures in fee metals. Since these modulus results and the data obtained from pole-figure studies must be internally consistent, it is appropriate to compile a brief summary of the experimental observations based on all available methods rather than on the pole-figure data alone as has been done in the past. The primary purpose of such a summary would be to yield a more precise definition of the experimental facts on the rolling textures of fee metals, and thus greatly facilitate our evaluation of various proposed theories in this field. The final section of this paper is devoted to this compilation of consistent, experimental facts and their application to the various theories. EXPERIMENTAL PROCEDURE Two 18-lb ingots of cathode copper of 99.99 pct purity were induction-melted under a nitrogen atmosphere in a graphite crucible and chill-cast into a steel mold. The ingots were repeatedly cold-rolled and annealed (I hr at 500°C) into slabs about 1 1/8 in. thick. Blocks 3 1/4 in. wide, 2 1/4 in. long, and 1.000 in. thick were machined from each slab. The rolling schedule used was the same as in the previous investigation1 and the final thickness of the sheet was 0.050 in. with a rolling reduction of thickness of 95 pct instead of 97.5 pct as in the previous work.' The compositions and temperatures of the cold baths used for the low-temperature rolling were as shown in Table I. After each pass the rolled strip was immediately immersed in the cold bath for about 1 min or until the bubbling of the bath had subsided. The modulus data were taken within 2 hr after the rolled strip was warmed to room temperature for the first time, so that effects due to recrystallization were minimized. The modulus specimens were in the shape of flat bars, 3 in. long, 4 in. wide, and 0.050 in. thick, cut with their long dimensions oriented at 15-deg intervals between the rolling direction and the transverse direction. The values of Young's modulus were deduced from measurements of the frequency at which these long narrow bars were set into longitudinal, resonant vibration as previously described.9 To excite the mechanical vibrations in the specimen, an electromagnetic drive similar to that employed by Thompson and lass" was used. The maximum in the amplitude of

Jan 1, 1968

By Shiro Ban-ya, John Chipman

Equilibrium in the reaction was investigated at temperatures of 1500°, 1550°, and 1600°C for sulfur concentrations up to 7.2 wt pct. Multisample crucibles contained the liquid alloys in a resistance-heated furnace using a technique especially designed for the study of more complex alloys to be reported separately. Modern free-energy data are used to correct the H2S:H2 ratio for dissociation of H2S and calculalion of the partial pressure of S2. Published data on the equilibrium are similarly corrected. Thermodynanzic treatment of the data employs the composition variable zs = nS/(nFe — nS) and the activity coefficient Gs = as/zs The data at 1500" and 1550°C are fitted by the equation log s = —2.30zs. Within the limits of experimental error the same coefficient is applicable to the data at higher temperatures. Equations are given for the free-energy change in Reaction [I] as well as for the solution of S, gas in the metal. The heat of solution of 1/2 s2 is -32.28 i2.5 kcal. Uncertainty in the free energy is very much smaller. For dilute solutions of interest in steelmaking, the activity coefficient of sulfur is unchanged from that listed in Basic Open Hearth Steel-making. DETERMINATIONS of the thermodynamic properties of sulfur in liquid iron by Morris and williams1 and by Sherman, Elvander, and chipman' provided a basis for control of sulfur in steelmaking processes. From the standpoint of understanding the chemistry of metal plus nonmetal in liquid solution they left several questions unanswered. The activity of sulfur in dilute solution at about 1600°C was well-established but temperature coefficients were uncertain, due at least in part to the use of the optical pyrometer and uncertainty regarding the effect of sulfur on emissivity. It appeared that deviation from Henry's law increased with increasing temperature, a most unusual behavior requiring either confirmation or disproof. These studies were based on experimental determination of equilibrium in the reaction: At high temperatures H2S is partially dissociated so that the gas mixture contains HS, S2, and S in addition to HS. At the time of the earlier studies the free energies of these constituents were unknown and it was therefore impossible to make adequate correction for dissociation. Observations on the effects of alloying elements by Morris and coworkers1, 3 and by Sherman and Chip-man4 enable us to assess the effects of alloying elements on the activity and to make corrections for incidental impurities in the binary liquid. These studies as well as a number of more recent investigations will be reviewed in detail after out own experimental results have been presented. It was our purpose in planning this study to avoid uncertainties regarding the emissivity of alloys and the errors of thermal diffusion which plagued some of the early attempts,5 by using a resistance furnace and thermocouple in preference to induction heating and optical pyrometer. Modern data on free energies of the gaseous species are to be applied to our data and to those of other investigators to obtain corrected values of K1 and of the activity coefficient and ultimately to relate the sulfur content of the bath to the equilibrium partial pressure of S,. Extension of the study to include ternary and complex solutions will be described in a later section. EXPERIMENTAL METHOD a) Preparation and Calibration of H2-H2s Gas Mixture. The source of hydrogen sulfide was a preparer mixture of 43 pct H2S, balance hydrogen, contained in a large aluminum cylinder. This was passed through anhydrone and through a microflowmeter. Hydrogen was passed through platinized asbestos, ascar-ite, and anhydrone, and through a capillary flowmeter. Argon was passed through copper wool at 500°C, then through ascarite, anhydrone, and a flowmeter. The flow rate of hydrogen was kept constant at 200 ml per min, to which an arbitrary amount of the hydrogen-hydrogen sulfide mixture was constantly added and then the prepared gas mixture was introduced into the reaction tube through a gas mixer. In certain experiments 200 ml per min of argon was added to the hydrogen-hydrogen sulfide gas mixture to increase the total flow rate of gas. The ratio of hydrogen-hydrogen sulfide in the inlet gas was checked for each run by chemical analysis. A sample of the gas taken from a bypass was bubbled through zinc and cadmium acetate solution (4 pct zinc acetate, 1 pct cadmium acetate, and 1 pct acetic acid) to remove hydrogen sulfide from the gas mixture, and the flow rate of the remaining hydrogen was measured by a soap bubble method to determine the volume of hydrogen. The amount of hydrogen sulfide absorbed in solution was determined by titration with iodine against sodium thiosulfate, with starch used as the indicator. The ratio of hydrogen sulfide to hydrogen in the inlet gas could be kept within ±2 pct in the range from 10-2 to 5 x 10"4 which corresponds to from 0.2 to 7.0 wt pct sulfur in liquid iron. b) Furnace Arrangement. Fig. 1 shows the furnace arrangement and the shape of the alumina crucible used in this experiment. A vertical-tube silicon carbide electric resistance furnace contained the reaction tube which consisted of two parts, the gas-tight

Jan 1, 1969

1910, hundreds of thousands of dollars of work and equipment in a 1500-foot shaft, crosscuts and pumping had found only copper-lean pyrite in two cross- cuts, and nothing in a third. Going aimlessly along the third crosscut one day, after looking at the barren face I happened to notice a dark spot in the white limestone, near the floor on one side. I picked, and found it was a little triangle of rich chalcopyrite. Next day I took Bill Gohring, then mine superintendent, in to see it. He said nothing else had succeeded so we might as well try that. The new drift broke into a full face of high grade copper ore in the first round, and continued in rich ore for 2200 feel broken only by a couple of short stretches of lean pyrite. The earlier crosscuts had happened to cut these lean areas. Q: Was there any single thing that called your attention to that little dark spot in the side of the Briggs crosscut, rather than to any other discolored spot? Joralemon: Nothing very definite. Maybe luck, maybe that indefinable subconscious thinking that

Jan 9, 1964

William Metcalf, Pittsburg, Pa. (communication to the Secretary*): I am greatly pleased that some one has at last reached what I have long regarded as the only rational explanation yet given of the reasons why steel hardens. Mr. Field claims originality; and doubtless he is entitled to it, but not to priority, mhich must be granted to Prof. John W. Langley.' The difference between them is that Langley says " Tension, probably molecular," and Field says " Tension, probably atomic "; in either case the vital thing after solution is tension. Mr. Field's argument carries with it the idea of increase of density with hardness; if he mill study the facts farther he will observe that the case is just the reverse; that is, the greater the hardness the less the specific gravity; it was just this fact that led Langley to his conclusion, in mhich I have always concurred. Field agrees with Langley that the first requisite for perfect hardening is complete solution of the carbon, not combination; and all of the facts agree with this conclusion. The fact that increase of hardness causes reduction of density was first brought to my notice some 40 years ago, when Major William Wade was testing Jones & Laughlin's cold-rolled iron, and I mas his assistant. We found the well-known increase of tenacity, compressive strength, torsional resistance, and hardness. Specific-gravity tests showed that the cold-rolled iron was less dense than the hot-rolled bars. Major Wade was so surprised at this result that he gave me a lot of samples to weigh, saying that he was not satisfied with

Jan 1, 1904

By Charles E. Wait

In the analysis of a set of interesting furnace-products belonging to the metallurgical cabinet of the School of Mines, I placed in the hands of one of my students a sample of litharge which gave the results quoted below. The collection of specimens from which this was taken, represents the products obtained in the blast-furnace treatment of argentiferous lead ores, also samples from the zinc process, and those from the cupellation of the enriched lead. The sample, when received, was marked "bismuth litharge," and was that obtained during the last stages of cupellation. It gave upon analysis the following : Per cent. Lead,.......85.36 Antimony,.......06 Bismuth ,........20 Copper,.....49 Iron,...... 69 Zinc,......18 Nickel,.....01 Silver,....2.94 Lime,.....36 Magnesia,....03 Silica,.....12 Sulphuric anhydride,. .32 Carbonic anhydride,. 1.25 Water,.....24 Oxygen,..,.7.80 99.95 At present I wish merely to call attention to the large percetage of silver present (equal to 857 ounces Troy per ton of 2000 pounds avoirdupois), and also to note two or three determinations that I have recently made, with a view to ascertain, if possible, the condition in which this silver exists. If I mistake not, it is usually assumed that silver exists in litharge in the metallic state; and it is, indeed, in the analyses of litharge, rarely expressed otherwise. This method of reporting the silver is, no doubt, due to the accepted statements that the oxides of silver are reduced to the metallic state at a temperature of 300' C. or less. The following experiments lead me to believe that silver exists in litharge, not entirely in the metallic state :

Jan 1, 1887

By E. J. Schmitz

This section was obtained last year during an examination of the iron-ore resources of the Rich Patch Mountain region and along Craig's creek valley. The geological members below the Oriskany and Lower Helderberg are exposed along the gap in a beautiful arch, while the higher formations appear in a more or less disturbed state on both sides of this arch, and are partly covered by dèbris. I have thought it of interest to the Institute to reproduce the drawing of this section at the gap which I made in my note-book at the time of my examination; those parts of the section, which lie at both sides of the arch, are only approximated. I give also a number of notes and measurements, referring to the Clinton formation and especially to the characteristics of the fossiliferous ore-seam opened in the various tunnels along the arch (see section). I. In Tunnel C: For the first 110 to 120 feet to second shute, we find the ore only here and there in small deposits, and interchanging with, or changing into, either a very siliceous limestone or a sandstone. About 10 feet beyond shute we have : Sandstone roof. Clay-slate, 211/2 inches Brown lean ore, 1 inch. Sandy clay, 3 to 31/4 inches. 1. Dark .brown ore, 3 inches. 2. Fossil-ore, changing into sandstone or very siliceous limestone, 2 inches. 3. Brown lean ore, 6 inches. Clay and slate below, 1 foot. 194 feet from entrance : Sandstone roof. Clay-slate, 4 inches. Clay 15 inches. Fossil-ore, 63 to 7 inches. Clay and ore, If inches. Lean brown ore, 2 inchea. Clay to bottom, 2 feet.

Jan 1, 1896

By Elwood Haynes

As in organic nature certain animal and vegetable forms have undergone modifications, and thus, as it were, fitted themselves to live in a new environment, so it has been found possible in certain instances to form new metallic combinations which are practically immune to the natural conditions that exist on the earth at the present time. A few of the metals, such as gold, silver, and the metals of the platinum group, are found native, but the commoner heavy metals are nearly always found in the form of oxides or sulphides. For a number of years I have made experiments with a view to finding certain metallic combinations or alloys which would not only resist oxidation and other harmful influences, but would also possess valuable physical properties, which would render them fit for special service. The first decisive step made in this direction was the discovery of an alloy of nickel and chromium in 1898. The properties of this alloy have already been described in a previous paper.' Immediately following the discovery of the nickel-chromium alloy, I produced an alloy of cobalt and chromium, which has likewise been described in the reference given, but the range of proportion between the cobalt and chromium is so great, and the combination is modified to such a marked degree by the introduction of other substances, that I have felt justified in reading another paper on this subject, describing more fully my researches in this particular direction. As early as 1907 and 1908,I made alloys or combinations of cobalt, chromium, and tungsten; cobalt, chromium, and molyb-

Jan 1, 1913

By J. W. Ristori

During the year 1940, production of crude oil in RiIexico totaled 43,914,000 bbl., or 2,776,000 less than in 1937, the year before expropriation. The 1940 output was I,2000,000 higher than in the previous year. In 1937, Poza Rica production accounted Declines in exports of Panuco crude, fuel oil and gasoline were recorded but these were more than offset by increased exports of 4,000,000 bbl. of Poza Rica crude, which was the approximate amount shipped to Sinclair during 1940 under the terms of the settlement. Over-all exports increased by 1,500,000 bbl. over the preceding year. The outstanding development regarding the destination of Mexican exports in 1940 was the increase of I0,000,000 bbl. in the exports to the United States. Exports to Germany ceased toward the end of '939 and to Italy in the second half of 1940. During the year 1940 the Sinclair interests and the Mexican Government settled their expropriation question. By the terms of the settlement Sinclair is to be compensated by cash payments and oil-purchase contracts. On Dec. I, 1940, Ada Camacho was inaugurated President of Mexico for a term of six years. Among his first acts following his election were: I. A proposal to change the Constitution to restore Supreme Court Judges' terms to life tenure. This has been ratified by both chambers of the Mexican congress and is now before the legislatures of the States of Mexico for ratification. The, taking away of the administration of the railroads from labor and restoration to the State.

Jan 1, 1941

By J. W. Ristori

During the year 1940, production of crude oil in RiIexico totaled 43,914,000 bbl., or 2,776,000 less than in 1937, the year before expropriation. The 1940 output was I,2000,000 higher than in the previous year. In 1937, Poza Rica production accounted Declines in exports of Panuco crude, fuel oil and gasoline were recorded but these were more than offset by increased exports of 4,000,000 bbl. of Poza Rica crude, which was the approximate amount shipped to Sinclair during 1940 under the terms of the settlement. Over-all exports increased by 1,500,000 bbl. over the preceding year. The outstanding development regarding the destination of Mexican exports in 1940 was the increase of I0,000,000 bbl. in the exports to the United States. Exports to Germany ceased toward the end of '939 and to Italy in the second half of 1940. During the year 1940 the Sinclair interests and the Mexican Government settled their expropriation question. By the terms of the settlement Sinclair is to be compensated by cash payments and oil-purchase contracts. On Dec. I, 1940, Ada Camacho was inaugurated President of Mexico for a term of six years. Among his first acts following his election were: I. A proposal to change the Constitution to restore Supreme Court Judges' terms to life tenure. This has been ratified by both chambers of the Mexican congress and is now before the legislatures of the States of Mexico for ratification. The, taking away of the administration of the railroads from labor and restoration to the State.

Jan 1, 1941

By C. G. Goetzel

E. V. Crane.*—I want to ask Dr. Goetzel concerning the control of atmosphere in heating and pressing. Was the heating and pressing done in the die, or were the two kept separate there? C. G. Goetzel.—The setup used for this investigation implied heating the die to the temperature at which the work was to proceed, introducing a preformed compact into the hot die. The atmosphere was supplied through an annular chamber from which it passed through two holes into the die cavity. E. V. CRane.—The compact was not preheated? C. G. Goetzel.—The compact was not preheated. Tee Chairman.—In the course of recent studies on the effect of time of heating upon the tensile strength and hardness, I have observed that there is often a maximum in tensile strength and hardness reached before complete homogenization has been attained. The magnitude of each mechanical Property changes rapidly with time in the early stages of sintering, the more so as temperature increases. For these reasons it seems that the comparison of values obtained by heating for the same time at a series of temperatures may be deceptive. Not only may those heated at higher temperatures give higher tensile readings, but the reverse may be true if the maximum in the tensile strength versus time curve has been passed. A better basis for comparison would be that of equal degree of diffusion. C' " Goetzel.—Thank you, Professor Rhines, for this interesting contribution. I would like to add here that I have noticed a similar effect with straight copper. There is, of course, the possibility that this maximum in hardness and tensile strength may be caused by work-hardening.

Jan 1, 1945