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By R. T. Bayliss

Although every mill-man of even limited experience in the amalgamation of gold-ores is probably aware that copper plates will in time become coated by the accumulation of gold-amalgam, it may be that many do not know to what extent this accumulation occurs in the treatment of ores dissimilar to those with which they are familiar, and under conditions foreign to those with which they have to contend in any given locality. The writer, therefore, feels relieved from the necessity of offering an apology for dealing with such an elementary subject, believing that certain facts in reference thereto, which have recently come under his personal observation, will be interesting to many, and possibly instructive to some persons engaged in the amalgamation of gold-ores. The facts hereinafter stated were observed in the 50-stamp "combination"-mill, owned by the Montana Mining Company, Limited, of England, operating the Drum Lummon mine, situated at Marysville, Montana. The material treated in this mill consists of quartz and ores of somewhat variable character, containing gold and silver in native form, as well as in chemical union with the sulphides of iron and copper. There is also present a little lead, some arsenic and antimony, and a little zinc. The last fair minerals, however, are of irregular occurrence, and but sparingly distributed throughout the ore, and yield only a trace in the analysis of the average material in this mill. The free gold, which is in a condition of fine division, and rarely visible to the naked eye, carries silver as an alloy; and the native silver, which is only occasionally observed, is present in the richer ores in wireand in leaf-form. Of the two precious metals, the ore worked during the past three years and ten months, the period under review, contained about 1/2-ounce of gold, and from 7 to 12 ounces of silver, per ton of 2000 pounds.

Jan 1, 1897

By R. L. Frink

I FEAR that my treatment of this subject may not, in all instances, meet the approval of those who read my opinion as to the utility and efficiency of pyrometers in the making of glass, or bottle-glass. It may be superfluous for me to add that this opening statement is based on over 15 years' experience in an endeavor to successfully apply pyrometers, or heat-measuring instruments, to glass-melting furnaces, particularly the type known as tank-furnaces, and that such endeavors have proved more or less futile. It is my desire, therefore, to herein set forth the problems encountered, hoping thereby to stimulate further effort in the successful application of pyrometers. It is my desire, also, to invite criticism of the methods used and suggestions from those who may have a wider experience, or who may have better methods. Fin. 1.-GLASS TANK FURNACE. In general, I believe that the inefficient application of pyrometry to the melting of glass in tank furnaces is not due as much to the instruments as to the conditions under which they must be used and the character of the medium in which they must reside. Most of those present no doubt, are familiar, at least in a general way, with the methods and apparatus used in the melting and making of bottle-glass, or glass that is formed into containers of various shapes and designs. Most of this glass is made in what is known as a tank furnace, these furnaces vary widely in design and construction. In general, they consist of a rectangular tank-like form, built up of fireclay blocks, and range from 2 by 4 ft. (0.6 by 1.2 m.) to 24 by 140 ft. (7.3 by 42.6 m.) with a depth of glass from 2 to 5 ft.; or a capacity of from approximately. 2 to 700 tons. Fig. 1 shows the general

Jan 9, 1919

By H. C. Kenny

The annealing or softening temperature of cold-worked copper is appreciably increased by almost unbelievably small amounts of silver. As indicated by some data in this paper, the softening temperature of high-conductivity, tough-pitch copper may be increased from 200" to 350" C. by the addition of only 15 oz. per ton (0.052 per cent) of that element. Because it has this higher annealing temperature as compared with the silver-free metal, silver-bearing copper finds considerable use in industry. For example, when hard-rolled copper is used in operations that involve soldering or tinning, silver-bearing copper insures against loss of strength, whereas silver-free copper becomes "dead soft." Yet—though several investigators, beginning with Caesar and Gernerl in 1916, have shown that small amounts of silver do definitely raise the softening temperature of copper—data are lacking on the problem: What is the specific influence of different amounts of silver on this temperature? It was to help in filling this gap in the knowledge of what might be termed "alloy coppers" that the data given herein were obtained. The softening of cold-worked copper depends, of course, on a number of factors, of which the composition of the material is only one. Other highly important factors are the degree to which the material is cold-worked and the time it is held at the annealing temperature. The method of cold working and the grain size of the metal produced are also significant. All these variables were taken into account in the investigation reported here, and the influence of silver on the electrical conductivity and on the working was also considered. The coppers used in the softening tests were Lake coppers melted and cast by the Calumet and Hecla Consolidated Copper Co. The ires were fabricated by the Roebling Wire Co. and the sheets were rolled at the Battelle Memorial Institute. Partial analyses of some of the coppers are listed in Table 1, with their electrical conductivities.

Jan 1, 1934

By Frederic Laist

IN the spring of 1931 an experiment was made at Anaconda with a small reverberatory furnace, with which was combined a roasting shaft. The arrangement is shown in the accompanying drawing (Fig. 1) and requires but little explanation. The general idea was to roast .flotation concentrates, mixed with the proper fluxing materials, by dropping them down a heated shaft, from which the calcines would enter the smelting zone of the reverberatory furnace through an opening in the roof. The hearth of the reverberatory was 3 ft. wide by 21 ft. long. The roasting shaft was 3 ft. square inside and had an effective height of about 20 ft. . The reverberatory furnace was arranged so that it could be charged either directly through the roof with regular hot calcines, in the usual manner, or by means of the shaft, at the top of which were a feed-ing arrangement by which cold flotation concentrates, suitably fluxed, could be fed continuously and a pipe through which cold air was blown in. Means were provided for distributing the feed over the cross-section of the roasting shaft. At first a mechanical arrangement was used but later it was found that a simple cone served the purpose equally well and gave less operating trouble. On account of the small size of the equipment, it was realized that absolute capacity and fuel consumption figures would mean but little. It was not to be expected that ratios comparable to those obtained in large furnaces could be gotten, and the only way in which any idea could be obtained as to the possibilities of the combination furnace was to run it in parallel with the reverberatory furnace charged in the usual manner and operating without the shaft. The results of such parallel runs are given in Table 1. The amount of oil burned in the reverberatory was purposely maintained at substantially the same rate during both runs in order that the benefits resulting from the shaft might be gaged.

Jan 1, 1933

By H. M. Boylston

METALLIC manganese was first produced in 1773, by Sven Rinmann, a Swedish mineralogist. In 1799 William Reynolds, of Ketley, England, obtained a patent on the use of manganese dioxide in the manufacture of steel, and in 1808 an English patent was granted to John Wilkinson covering the use of manganese ore, or manganiferous ore, as an addition to iron ore in the blast furnace for the production of a superior grade of pig iron. Karsten showed in 1816 that manganese increased the hardness of iron without decreasing its malleability or toughness, while it caused pig iron to be more white in fracture and more fusible. The first practical application of manganese to steel-making, however, is attributed to Josiah Heath who discovered in 1839 (less than 90 years ago) that manganese conferred upon steel the properties of being more easily worked and welded under the hammer. When Bessemer invented the pneumatic process of steel-making which now bears his name he was at first successful because, as it afterward developed, he was using. a Swedish pig iron high in manganese. When his supply of this material ran out, he used a low-manganese pig from English sources and failed signally to produce a steel which could be rolled, while his Swedish licensees were continuing their successful application of his method. And it was not until Robert Mushet, in 1856, suggested the addition of manganese in the form of spiegeleisen to the molten product of the converter that success again came to Bessemer. In 1866, William Siemens patented the use of ferro-manganese as an addition to molten steel to counteract the bad effects of sulfur. It was in 1888, that Robert Hadfield published at some length his account of the effect of manganese as an alloying element in steel and described the unique properties of the now famous Hadfield manganese steel containing about 12 to 14. per cent. manganese and 1.25 per cent. carbon.

Jan 5, 1927

CONTENTS PAGE DANIELS, SAMUEL, LYON, A. J., and JOHNSON,. J. B.-Casting and Heat Treatment of Some Aluminum Copper-magnesium Alloys 1 ELLIS, O. W. and SCHEMNITZ, D. A.-Experiments on the Heat Treatment of Alpha-beta Brass : 4 ENOS, GEORGE M. and ANDERSON, ROBERT J.-Coatings. Formed on Corroded Metals and Alloys 5 COMSTOCK, GEORGE F.-Notes on the Hardness of Heat-treated Aluminum Bronze 6 Casting and Heat Treatment of Some Aluminum Copper-magnesium Alloys Discussion of the paper of SAMUEL DANIELS, A. J. LYON, and J. B. JOHNSON, presented at the Milwaukee Meeting, October, 1924, and issued, as Paper No. 1350-N, with MINING AND METALLURGY, July, 1924. D. HANSON and M. L. V. GAYLER, Teddington, England (written discussion).-At the National Physical Laboratory, the writers have made a number of researches on the relation between the constitution and mechanical properties of aluminum alloys of various types; the results obtained were in good general agreement with those of the authors. The writers, however, did not think that increasing the copper content of sand-cast low-copper duralumin to 4 per cent. necessarily caused a drop in the elongation to 1.5 per cent., as stated on page 9. In the case of sand-cast copper-aluminium alloys they had obtained much greater elongation, in some cases as great as 13 per cent. in heat-treated castings. For example, in a sand casting containing 3.5 per cent. of copper, a strength of 12 tons per square inch and an elongation of 13 per cent. were obtained; in a casting containing 4.5 per cent. copper, a tensile strength of 13 tons, and an elongation of 9 per cent. were obtained. These values were the maximum; the elongation varied considerably, being as low as 5 per cent. in some cases. In the writers' opinion, such variations are due more to unsoundness in the sand casting than to any other cause.

Jan 1, 1925

By Edgar Newhouse

THE lead smeltery at East Helena, Mont., controlled by the American Smelting & Refining Co. since 1899, has been in continuous operation for the past 25 years. Most of the old smelting and roasting practices have been superseded by newer and more modern methods, but on account of the difficulties involved in changing the original construction, some of the methods in use of handling materials are not the most modern. This plant, however, is particularly interesting as being one of the few essentially lead smelteries in the United States. At Federal, Ill., Collinsville, Herculaneum, and possibly other places, similar work is being done, but it is doubtful whether any of them produces as' much lead as the East Helena plant, whose monthly production averages 6,500 tons. The situation, 5 miles east of Helena, is convenient to both the Great Northern and Northern Pacific railroads, while the electric power is obtained from Canyon Ferry, 12 miles east on the Missouri river. Local quarries supply the requisite amount of lime rock, Which the contracts require to be crushed to 5 in. Of the 450 men on the monthly pay roll, a census showed 200 Austrians, 110 Americans, and 30 Italians, the balance being made up of miscellaneous nationalities. The ore supply is mainly derived from the Coeur d'Alêne mines in Idaho, and consists of crude ore, coarse and fine concentrates, middlings, and slimes. About one-half of the total output of the Coeur d'Alêne camp is sent to East Helena. An average analysis of these ores gives approximately 40 per cent. lead and 11 per cent. sulphur. Local shipments, varying, from month to month, are mostly highly siliceous gold and silver ores carrying little lead. Small shippers, leasers of old mines, and prospectors are very numerous throughout Montana, and it is the policy of the company to encourage these men by every possible means, including the free sampling and analysis of their ores and aid in the development of their mines and prospects whenever their results show promise.

Jan 8, 1914

By R. A. Bowen

THE Montreal mine, operated by the Montreal Mining Co., is four miles west of Ironwood, Mich., in Iron County, Wisconsin. It is the westernmost producing property on the Gogebic Iron Range of the Lake Superior district. Its production is 4000 tons of hematite per day from an average depth of 2300 ft. This tonnage is hoisted through a five-compartment vertical shaft. Several mining methods are in use but in the larger orebodies the method is sublcvel caving. ORE OCCURRENCE AND CHARATERISTICS The main orebodies of the Montreal mine lie in eastward-pitching troughs formed by the intersections of intrusive dikes with impervious members of the iron formation. The formation has an average width of 425 ft., strikes east and west and dips north at approximately 62°. The dikes dip south at 45° and bear north 20° from the strike of the formation, making the intersections with various members pitch east at 16°. The dikes are not continuous across the formation but are interrupted by a longitudinal bedding fault, which has a throw of 380 ft. vertically and 885 ft. horizontally. North of the fault zone the formation is called "hanging," south it is called " footwall" formation. The faulting has created two ore-bearing horizons; viz., at the inter- section of hanging dikes with the slate members and the foot dikes with the quartzite footwall. In each formation the main ore-bearing member consists of wavy beds of hard chert interlaid with hematite. In the most productive part of the mine, where the sublevel caving method is employed, a hanging-formation dike lies in juxtaposition with a footwall dike and the iron formation carries ore in certain sections from the quartzite footwall to the hanging dike. Here a horizontal section of the orebody may be 300 to 400 ft. wide for a length of 150 ft. or more and tail out lengthwise in both the foot and hanging formations. The footwall ore section is much longer than the hanging wall because of the orebody's greater height above the "pitching dike."

Jan 1, 1938

By Frank M. Brewster

The handling of congealing oils and paraffin is a serious problem in the Appalachian fields, particularly because the small amount of oil produced per well makes the removing of paraffin a very costly operation per barrel. Few operators realize or have any means of knowing just how much production is lost on account of paraffin depositing over the face of the sand and plugging the pores of the sand; but where paraffin has been removed the production increases indicate that this loss has been considerable. Many operators believe that paraffining is confined to the tubing and pumping equipment, but it is evident that the most serious damage occurs on the face of the sand and a short distance back in the pores. This paper is an attempt to disseminate information on methods and processes in use in the Eastern fields for combatting losses of production and operating difficulties caused by deposition of paraffin in the pores, on the walls, on the tubing and on other pumping equipment. Mills1 covers this subject so thoroughly that excerpts, abstracts and quotations from his work have been used freely in this paper. Nature oF Paraffin Mills states: "The so-called paraffin that collects in oil wells, and in the pores of the producing sands immediately around the wells, is generally made up of amorphous wax or uncracked paraffin, asphalt, or other gummy hydrocarbons mixed with more or less water, oil and inorganic silt. Some of the samples of this paraffin collected from oil wells in different fields and examined by the Bureau of Mines contains as much as 20 per cent. by weight of water and inorganic silt, whereas other samples are composed entirely of waxy hydrocarbons and oil. The inorganic silt accompanying this 'paraffin' is mostly fine sand, clayey materials, common salt and finely disseminated precipitates of calcium and magnesium carbonates. Sulfates of calcium, barium and strontium are less common constituents of paraffin.

Jan 1, 1928

By R. W. Raymond

The death of Mr. Stetefeldt, which occurred at Oakland, Cal., March 17, 1896, was a surprise, as well as a sorrow, to many of his friends and professional colleagues. In the Engineering and Mining Journal of March 28th, I published an obituary article, the substance of which, modified and enlarged by later information, forms the basis of the present biographical notice. I am indebted to Mr. Albert Arents, Alameda, Cal., and Mr. 0. H. Hahn, Monterey, Mex., life-long friends, and to Miss Pauline Anacker, of Gotha, Germany, a cousin of the deceased, for details which I could not have obtained elsewhere. Carl August Stetefeldt was born September 28, 1838, in the village of Holzhausen, in the duchy of Gotha, Germany, where his father was a Lutheran pastor. He was an only son, and (after the early death of a sister) an only child. In his boyhood he is reported to have been physically delicate, but mentally precocious. In 1847 his father was transferred to Hörselgau, near Waltershausen, where, besides discharging his pastoral duties, he kept a select private boarding-school, in which a few pupils received a training preliminary to the " gymnasial" course. Among these pupils (one of whom was the now famous Dr. Knorr, the discoverer of antipyrine) he included his own son, who, thus carefully prepared, entered in 1852, at the age of fourteen, the gymnasium at Gotha. The records of the gymnasium bear witness that his conduct in and out of school was " blameless," and his attention to study good." But his career as a "gymnasiast" was marked by an act of rebellion probably more startling then than it would be now. Being much more strongly attracted by the natural sciences than by the dead languages, he conceived a special aversion to Hebrew, and engaged in a conflict with the professor in that department, out of which he seems to have come victorious. At all events, he was not obliged to pursue further

Jan 1, 1897

By W. Lawrence Austin

It has been suggested to me that some data, bearing on the treatment of silver ores in Southern Arizona, would be in accord with the objects of the present meeting. I have, therefore, made a few notes, gathered from practical experience at some of the best known works of that district. Presuming the general arrangement of a silver mill to be familiar to members, the subject having been repeatedly brought to the notice of the Institute, it is my aim in the following description of the modus operandi at the different mills to which I would invite your attention, to give simply such salient points of the apparatus as have a direct bearing upon results, together with the cost of materials, labor, etc. I have gone somewhat deeply into detail in my descriptions of machinery, thinking that possibly some of our members engaged in this branch of the profession might find something of interest among them. In an industry such as silver milling, where the various works are scattered over a vast extent of territory, and the conditions under which results are obtained are subject to the greatest variations, it is essential to go into rather minute details in describing plants, processes, etc., in order to afford a clear idea of the operations. Not only should results be given, but also the means by which such are attained. The milleralogical and chemical constituents of the ore, and its physical properties, throw a flood of light upon the success or failure of a process Figures representing totals I have subdivided as much as possible, so that the cost per ton for labor, castings, chemicals, etc., are apparent. Unless all these Factors are known, no accurate comparison can be drawn, since in this branch of metallurgy, more perhaps than in others, the weakness of any one link in the chain of operations demoralizes the remainder. That it costs $10 to mill in one

Jan 1, 1883

By M. Gensamer

ALTHOUGH a large number of X-ray photograms of cold-rolled steel have been published, two circumstances have led to the experimental work reported in this paper. The first is that no complete study, making use of the pole-figure method of Wever1, has been made of cold-rolled low-carbon steel. Wever has published pole figures of mild steel sub-jected to plane parallel deformation1,2 and undoubtedly he has applied the method to cold-rolled mild steel, but the authors have not found these data published. Kurdjumow and Sachs3 have applied the method to the study of rolling and recrystallization textures in electrolytic iron; their results will be referred to later. The reason for this dearth of papers using the pole-figure method is obvious; a greater number of photograms and more analytical work (although this work is quite simple and straight-forward) are required to construct a pole figure than most investigators have felt worth while, despite the fact that no other method of which the authors are aware will satisfactorily depict the orientations of the crystal-lites in a polycrystalline aggregate. The second circumstance that led to the work reported in this paper was the appearance of a paper by Wayne A. Sisson4 on the same subject. In his valuable study of the factors influencing the development of pre-ferred orientations in cold-rolled mild steel, Sisson made one observation that required confirmation; that is, that at some stage of the rolling proc-ess the type of preferred orientation changed from the type that gives a photogram characterized as a "six-point" X-ray pattern to that known as a "four-point" pattern. A similar observation had been made by Tam-mann and Heinzel5, who studied the orientations developed in the rolling of steel by the specular reflection of light from the etched surface of rolled samples. These workers also found that the type of preferred orientation

Jan 1, 1936

By Leonard Greenburg

The American literature in the field of dust sampling and analysis has been growing rapidly since 1915. Studies made since that time clearly indicate that there are three fundamental factors that determine the production of lung pathology due to dust inhalation. These are the duration of exposure, the chemical and mineralogic nature of the dust and the concentration of the potentially harmful dust. In the estimation of the amount of the potentially hazardous dust there are essentially three problems involved: (I) a determination of the size of the hazardous dust; (2) determination of the most satisfactory apparatus and technique of sampling, and (3) the most satisfactory method of analysis. A complete study of the literature shows that industrial dust varies ill size from ultramicroscopic particles to those larger than lop in diameter and that relatively few particles are found over 5u in diameter. Approximately 10 to 25 per cent are less than 0.811 in diameter and the median size as a rule is found to lie between 1.25 and 1.75 microns. From the point of view of lung pathology the particle sizes of most importance lie between 0.5 and 5u. Of all the instruments for sampling dust the Impinger apparatus is the only one that will sample a larger body of air satisfactorily with small control errors and high efficiency in both low and high concentrations of dust. The Owens apparatus has the advantage of being more portable and somewhat easier to use but it does riot permit of the sampling of large volumes of air. It has a low efficiency in high concentrations of dust and does not permit dust weights to be obtained. From the point of dust-counting technique the author points out that in 1922 considerable experimentation with dark field and oblique illumination resulted in the conclusion that such methods were not readily duplicated from day to day and therefore yielded somewhat erratic results. Changes in the amount of illumination produced variations of several hundred per cent in dust counts obtained with dark ground

Jan 1, 1934

By B. L. Sackett

In a general way, the situation in copper smelting is quite similar to that of lead smelting. In other words, the introduction and successful flotation of copper ores has tended to decrease greatly the tonnage to be handled by the smelter and therefore has resulted in curtailed smelter operation. However, copper production has increased rather than decreased. The general effect of flotation has been to decrease the number of furnaces operating, but it has also increased to a considerable extent the difficulties in handling the material, just as was outlined in the case of lead smelting. In copper smelting, the flotation concentrates must be roasted and prepared for the reverberatory furnace. Handling Flotation Concentrates The handling of copper flotation concentrate, which is more or less wet and mucky, is more difficult than was the handling of the old gravity concentrate. Also, the roasting of the concentrate and the handling of the calcine produced is more difficult. That is mainly because the material is extremely fine and the tendency to higher dust losses is greatly increased. The draft in the roasting furnaces must be kept as low as possible, and the feeding of the calcine into the reverberatory furnace must be done carefully, so that dust losses may be kept at a minimum. Transition Stages oF Concentration and Smelting The general process through which the copper smelter has gone as a result of flotation has been somewhat as follows: In the relatively old days, when copper ores of low grade were first treated, a large number of furnaces were required, and naturally comparatively poor recoveries were made. Also, the profits on low-grade ores were small and the handling of those ores was possible only because of the large tonnages. Then came gravity concentration, which was a great improvement but which only incompletely removed the gangue material, the insoluble and the iron, from the copper ore, and made comparatively poor copper recoveries. This still left a considerable amount of insoluble and iron, as well as the copper itself, to be treated at the smelter.

Jan 1, 1928

By C. A. Edwards

Following a brief introduction, an outline is given of the four main conditions in which gases may be associated with metals; namely, (1) adsorbed gases, (2) dissolved gases, (3) gases in chemical combination, (4) gases entrapped in blowholes or cavities. Adsorption is essentially a surface phenomenon and is regarded as the attachment of outside molecules or atoms to the exposed free valencies of the atoms comprising the surface layers. In many cases where adsorbed films of gas are formed this is accompanied by a process of diffusion of the gas into the metal itself. This is particularly true in respect to iron and hydrogen, and experiments have shown that there is no difference between the rate at which hydrogen diffuses through a single crystal of iron arid through the same material after it has been recrystal-lized into a mass of small crystals. This does not prevent a somewhat greater concentration of gas at the boundaries of adjacent crystals, nor does it mean that the effect of the gas will be the same at the boundaries as it is within the body of the crystals. Indeed, under certain conditions, iron is rendered very brittle at the crystal boundaries, as shown in experiments by Pfeil with samples of almost pure iron. Much work has been done by many investigators concerning the temperature and conditions under which dissolved hydrogen, in particular, can be at least partially removed from different metals. With iron, the hydrogen that has diffused into the metal as a result of acid attack by pickling or by electrolytic deposition of the gas on the metal is partly removed by exposing the metal to the atmosphere at ordinary temperatures. Considerably more can be eliminated by raising the temperature, and even greater quantities by jointly raising the temperature and reducing the pressure. Annealing at suitable temperatures completely removes the bad effects of excessive mounts of hydrogen dissolved in or associated with iron. This is shown by the data plotted in Fig. 1, giving values for electrolytic iron sheets after annealing at temperatures between 250" and 950" C. The hydrogen brittleness is rapidly diminished at

Jan 1, 1935

By John Henry Harden

IT appears that in the earlier days of anthracite coal mining, 1824-25, the Lehigh region mined 76 per cent. of all the coal sent to market. During the same period Wyoming sent 12 and 5 per cent. respectively, whilst the Schuylkill sent 11 and 18 per cent., the number of tons marketed being in those days very small indeed. In the year 1828 the Schuylkill region mined over one-half of all the coal sent to market, and continued to do so for thirty years (with the exception of the year 1831), until 1858 ; since that date the pro¬duction has declined very steadily in comparison with the other regions, until, in 1876, it was only 34 per cent. Wyoming, in the year 1820, was mining 40 per cent., but the production of all the regions was very small ; in six years it declined to 5 per cent., increased to 34 per cent. in 1831, declined to 10 per cent. in 1838. Since which time the increase has been gradual, until 1873-75 Wyoming produced over 50 per cent. of all the anthracite coal sent to market. In 1867 the production exceeded that of Schuylkill, and has continued to do so since that time. In the year 1876, during the existence of the " coal combination," Wyoming lost 9 per cent. ; during the same time Lehigh gained 7 and Schuylkill 2 per cent. over their relative production of the preceding year, the decrease of Wyoming being two and a half million tons, the increase of the Lehigh one million, the decrease of the Schuylkill nearly three-quarters of a million. The extraordinary production of the Lehigh region at a time of decreased demand and in opposition to an agreement with the other regions to limit the supply to the supposed demand was the cause of the disagreement which ultimately broke up the combination of the great coal-producing and carrying companies. The Lehigh region produced very steadily, from 1829 to 1854, an average of about 22 per cent. of the whole production. From 1854

Jan 1, 1877

AT THE beginning of November, Mussolini had firmly established himself at the head of the Italian Government. He himself referred to the ascendancy of the Fascisti as the result of a revo-lution and bluntly informed Parliament that it was to vote, as a matter of form, as he ordered, or else be dissolved. One of the great consequences of these events in Italy was the impetus that they gave to simi-lar movements in other countries of Continental Europe. Another great event of the month in world affairs was the repudiation by the Turks of the Mudania agreement and their notification to the Allies that the latter must evacuate Constantinople and allow the Dardanelles to be closed. This had the effect of once more consolidating Great Britain, France and Italy in so far as this question is concerned, and there was prompt refusal to accede to the demands of the Turks. With the advent of November, both the United States and Great Britain were in- the throes of political contests. The result of the American election was a landslide against the administration and especially was it an expression of agrarian discontent and a declara-tion in effect that our domestic affairs are not good in spite of political representations that they are. In Great Britain, the Conservatives were put in power by a substantial majority in Parliament, but the fact that the Labor party became numerically the second party instead of the Liberals and that it polled about 40 per cent. of the total popular vote affords ground for misgivings, especially when it be considered that the Labor party was standing on distinctly socialis-tic and communistic principles. In Russia, there was a sitting of the Third Interna-tionale, to which Lenin in a speech made a quasi-confession of the failure of the communistic experiment in Russia. He admitted, moreover, that Russia could not industrially reconstruct herself without capitalistic help. Nationally the country is making progress. During November, the Far Eastern Repub-lic surrendered to the Soviet, which thus carried Russia back to the shore of the Pacific.

Jan 12, 1922

By W. S. Ayres

THE boiler from which these stay-bolts have just been obtained was that of the locomotive Catasauqua, Lehigh Valley Railroad, built at the company's shops, South Easton, Pa., in 1864. The iron is Lowmoor, and has been in use nearly ten years. The stay-bolts have become highly crystallized from some cause, and are very brittle, only requiring three blows of an ordinary machinist's hammer to break them. On the other hand, when annealed they are remarkably tough, as shown by the doubled sample. The majority of the broken bolts were found to be along the curve of the shell from a to c, Fig. 6. All of them were broken just inside the shell, and in no case next the fire-box. The fractures seen to have been of slow procedure, beginning at the top of the bolt, gradually working deeper and deeper until the pressure of steam overcame the tenacity of the remaining parts. Unequal contraction and expansion of the parts of the boiler seems in this case to be the only existing cause for a fracture. We cannot, from the data obtained, prove to an absolute certainty the manner in which the combined forces generated by the unequal contraction and expansion of the parts have arrived at their resultant work ; but we can, from these data and from existing circumstances, arrive at what seems to be a fair supposition, and thus at least anticipate the truth. The contraction and expansion in locomotive boilers has a large range between its extremes, and is very variable, both with reference to time and to their component parts. The shell and fire-box do not, perhaps, at any time, contract and expand at the same rate, nor proportionally ; but, on the contrary, owing to the great changes in temperature that take place both in the atmosphere around the shell, and in the fire in the fire-box, their condition is often changed suddenly, and widely from that which they just previously had. This racking tendency produces strains in the different parts, and it is fair to suppose that the continual motion of the two

Jan 1, 1874

By A. M. Nicholas

WHEN attempting to lift mill pulp containing a considerable percentage of wolframite, in an ordinary bucket elevator, difficulty was encountered from the tendency of the tungsten minerals to settle, on account of their high specific gravity. Lifts not exceeding 20 ft. (6m.) could be accomplished without particular difficulty, because there was insufficient time for consolidation of the heavy minerals in the bottom of the bucket; but with higher lifts, the heavy tungsten minerals would settle so solidly that when the bucket turned over at the top of the elevator the contents could be only partially dumped. In this case it ,was necessary to lift the material a distance of 34 ft. (10m.); hence some means had to be adopted to prevent settling, at least to such an extent that the material could be dumped from the buckets. To reduce the carrying time to a sufficient extent would have required a belt speed of 475 ft. (144.7m.) per minute, which was not feasible. It was decided to try, by vibrating the belt about midway of its span, to keel) the material sufficiently agitated during elevation to prevent settling. Underneath the rising side of the belt was placed a 12-in. (30.48-cm.) idler pulley, 18 ft.-(5.5 in.) up in the total lift of 34 ft. The idler pulley was set eccentric by 3/4 in. (19 mm.) and it was hoped that the vibration thus imparted to the belt, running at a speed of 280 ft. (85 m.) per minute, would prevent settling in the buckets. It was found that the pressure of the belt on the idler, due to the small inclination of the elevator, was not sufficient to overcome sliding on the idler, and the agitation was insufficient to accomplish the desired purpose. The idler was then connected to the drive shaft of the elevator through an intermediate pulley, gearing down to a speed of 20 r.p.m., so that a positive vibration was imparted to the belt; this imparted enough motion to the belt to prevent settling and the contents of buckets clumped satisfactorily.

Jan 2, 1918

By Walter Miller

The broad picture of petroleum refining engineering during 1934 continued to show a tendency in the direction of highly specialized processing improvements, particularly in manufacture of lubricating oil. The slowing up of the trend toward higher octane products in non-premium gasoline noticed in 1933 was definitely established as a fact by 1934 development, with just a slight indication of recession. No outstanding engineering achievements can be credited to 1934 in refinery cracking, unless the completion and successful operation of the 30,000-bbl. crude capacity combination cracking and skimming unit at Texas City, Texas, and a 20,000-bbl. similar unit in the East can be listed as such. Development and improvement was largely a continuation of previous lines of endeavor. Such trend as there is shows a continnation in the direction of very large integrated skimming and cracking units. A lessening of the cost of ethyl lead, coupled with the reaching of the octane number "ceiling," kept the subject of "reforming" low-octane gasoline into high-octane products pretty well in the background. Considerable interest, however, was shown during the year in cracking and polymerizing of refinery gases into high-octane motor fuel. The commercial development and application of this activity was greater in 1934 than during any previous year. Fair yields of gasoline of satisfactory stability and high antiknock value were reported, ranging from 2 to 8 gal. per 1000 cu. ft. of fixed refinery gas, yields varying with both the nature of refinery gas treated and processing methods. Assuming economic feasibility, regarding which there is still difference of opinion, gas polymerization offers the industry a possible outlet for its gases more in keeping with its basic chemical composition and value. The increased interest of railroads and heavy-duty truck and tractor manufacturers served to focus more attention on diesel fuels. The publicity given the Union Pacific diesel train, the Burlington "Zephyr" and others operated on special diesel fuels served to revive the intimations and fears of several years ago as to the ultimate replacement of the gasoline motor by diesel engines in even the passenger car field. How-

Jan 1, 1935