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By V. S. Swaminathan

This year, Great Britain is looking back over a century to August 14, 1850, the day when the first "Act for the Inspection of Coal Mines" was passed in that country, an act which signaled the end of over two hundred years of hitherto uncontrolled and dangerous mining practices. It was back in the time of Queen Elizabeth that . thousands of pounds were invested in mining, particularly coal mining in England and Scot- land. By 1640 there were collieries producing 10,000 to 25,000 tons of coal per year. In the seventeenth century the Tyne district coal industry was organized into powerful partnerships, and coal took an even larger part in industry, as a source of power and as fuel for the iron industry. In the early 19th century a "phenomenal, almost devastating expansion" characterized Britain's coal industry, and it was sparked by a 111 pct in- crease in the population of England and Wales in the first half of the century. Coal production for those 50 years increased 470 pct and pig iron production was up 946 pct for the period 1801-51.

Jan 1, 1950

By Sir John Cadman

IN THE changed circumstances which now confront the world, an international open-door policy is the only way to keep pace with the world's demand for oil. You may rest assured that as far as the British Empire is concerned, American capital for the develop-ment of oil resources is welcome, and little obstruction will be found in the way to permit the use of foreign capital in the group of countries which constitute the British Empire. In the war days we worked in close cooperation and harmony, but in disbandment of the Petroleum War Service Committee, when the war ended, I feel that it left its task unfinished. In the wake of war there appeared a ghost of war-time conditions in the form of belief that Great Britain was straining to corner the petroleum resources of the world. I am certain that if the war-service committee had continued its work in the period of reconstruction the real story would be known and this sinister ghost would have long since vanished before the truth.

Jan 2, 1922

By J. A. Gay

BRITISH success in extracting significant quantities of germanium from gas works flue dusts has been one of the prime forces in promoting similar research in the United States. Pittsburgh Consolidation Coal Co. and Pennsylvania Coal & Coke Co. are two of the larger U. S. firms with germanium from flue dust research programs. British interest in germanium started in 1933 when V. M. Goldschmidt reported that some coals from the Yard Seam of Northumberland and Durham contained 30 to 50 ppm of germanium.

Jan 8, 1953

By J. C. Jaeger

The study of brittle fracture of rocks has been a much neglected subject until quite recently and now is in a state of transition and rapid development. Historically, three methods of testing were used by engineers: uniaxial tension, bending, and, by far the most common, uniaxial compression of cubes. This latter was probably adequate for engineering requirements, but from the last century onwards there has been a demand from geologists for a study of the properties of materials under conditions comparable with those at depth in the earth's crust. King1 remarked that "in engineering practice a cube of the material is put into a testing machine and the stress required to crush the cube is measured. This gives the limiting stress difference for the material so long as the boundary conditions are similar to those existing during the test . . . this may by no means be the case when the boundary conditions are very different from those existing in the test, for instance, in the case of rupture in the neighbourhood of a cavity. . . ." Despite this very clear statement of principle, many writers until recently (e.g. Jeffreys2 used the uniaxial compressive strength as a measure of the 'strength' of rock. In the last century (Becker 3, it was both conjectured and, for some rocks, known qualitatively, that plastic deformation could occur under confining pres- sure; the demand from geologists has been for the study of flow rather than fracture of rocks.. From the time of von Karman (1911) and Böker5 (1915) onwards, apparatus has been built which could provide confining pressures sufficient to make some rocks plastic. Many experiments tended to be made on rocks such as marble, which readily become plastic, and the general tendency was to make relatively few experiments in the brittle range. This is particularly true of many experiments on combined stresses. As a result of this, there is not sufficient data to provide adequate information

Jan 1, 1967

By C. L. Dake

AN insistent and steadily growing demand is evident for the broadening of undergraduate curricula in engineering. Among suggested additions are training in public speaking, report writing, business law and contracts, accounting, finance, money and banking, scientific management, economics, social and labor problems, psychology, and ethics. The demand for these subjects comes from the older engineers and from the industries that employ our graduates. Of course, many of the men who suggest such changes are influenced largely by their personal needs and contacts, but the demand is sufficiently widespread to merit serious study by educators. In fact, many educators themselves concur in the proposals for broader training. These matters were examined intensively a few years ago in an exhaustive study of engineering education. Opinion at that time was rather strongly against any profound change. Since then, however, the whole economic system has undergone violent disruption. Even if recommendations made a few years ago were appropriate to the conditions then- obtaining, the enormously changed conditions of the present make advisable a further careful study of this problem. In recent years, mergers, to reduce costs, have sharply limited the number of engineers employed and have thereby intensified the struggle to secure positions. In this stiffer competition, engineers with the most adequate training undoubtedly fare the best.

Jan 1, 1934

By E. J. Horwood

The varying physical character and large extent of the Broken Hill lode necessarily involve the employment of a variety of underground methods. The lode had its origin in an extensive fault plane traversing metamorphosed schists conformably, as a rule, with their beds of stratification. The underground waters carrying minerals in solution deposited their contents. in the original cavities formed by the faulting action, and in the enlargements of these cavities due to dynamic forces brought to bear on the rocks, more especially on the hanging-wall side of the fault, This deposition was supplemented by metasomatic replacement of a portion of the original rock contents by the argentiferous sulphides of lead and zinc which form the staple products of the district. Although the orebody is practically continuous throughout the mines, its width varies greatly, ranging from a few feet to about 350 ft. The widest portions occur in conjunction with huge folds in the inclosing country rock, almost exclusively on the hanging-wall side. The ore it these folds pitches to the south in the southern half of the field, and to the north in the northern half; there are, however, undulations in these ore channels evidently due to compression of the rocks in the direction of the channels. In the earlier days, before the orebodies had been opened up: vertical cross-sections across these bulges in the hanging wall gave the lode the appearance of the "saddle formation," so well exemplified at Bendigo in Victoria; but subsequent development of the ore channels ha; long since proved that the formations in the two districts are entirely different. The depth reached by the zone of complete oxidation of the sulphide, varies from about 250 to 550 ft. from the original outcrop while partial oxidation extends in places below the 1,000-ft. level. The result of oxidizing influences has been the production of ore of every grade of cohesiveness, from that of dry sand to that of hard compact rock.

Jan 1, 1916

Conservatively, there are a half million square miles in Australia just like it, this spot near the western border of New South Wales. Space and distance are the elements. Mulga tree and salt bush, silvery under the sun, hug the ground too close to make welcome shade. To the east a wrinkle on the empty plain marks the line of lode, the Broken Hill bonanza. Strangely, the outback stops at a cyclone fence close by the ridge. Beyond, the peculiar island continent vegetation flourishes with the same frosty patina of the mulga and the salt bush. A city of 30,000 people is hidden behind the screen of vegetation. Once, the city was ugly and the people miserable from marching, flying sand. Now with a protective screen of vegetation, it is an oasis in the outback. The secret of the oasis is the fence. All regeneration plans failed until it was built to keep kangaroo, rabbit, sheep and man from destroying the plantations.

Jan 10, 1964

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 J. H. Jensen

Bromine is the intermediate member of the halogen family of elements between iodine, a solid: and chlorine, a gas. The name is derived from the Greek "bromos," meaning stench. Bromine is the only nonmetallic element that is liquid at room temperatures with a melting point of -7.2" C and a boiling point of 58.78" C. Reddish brown in color, it dissolves easily in water to yield a red solution. Bromine volatilizes at ordinary temperatures to a red vapor that is very irritating to the eyes, nose, and throat. Density of the liquid is 3.12 and gas weighs 7.59 gpl at standard conditions. As the element is highly active, it exists in nature only as bromide compounds. Bromine was discovered by Antoine Jerome Balard in seawater bitterns in 1826 and first prepared in quantity in 1860. Distribution Bromine is widely distributed in nature and compounds occur in solution in natural brines, in seawater, saline lakes, oil and gas well brines, and in evaporite chloride minerals. The concentration of bromine salts ranges from 60- 65 ppm in seawater to several thousand ppm in oil well brines and saline lakes. The distribution of bromine in marine evaporite minerals and in the solutions from which they crystallized was determined many years ago by H. E. Boeke (1 908). Theoretical aspects regarding the geochemistry of bromine have been published in numerous papers (Raup and Mite, 1969). Bromine occurs in solid solution in carnallite and sylvite associated in potash de- posits; in halite in salt beds; salt in oil shales; and in trona deposits. Its presence is useful as a guide in geochemical exploration. The analysis of small amounts of bromides in the presence of large amounts of chlorides is discussed by W. Schwerdtner (1963). Manganese, iron, and iodine may interfere with the determination. Other analytical methods are discussed at length in the literature (Stenger and Atchison, 1964). Sources and Reserves The sources and reserves of bromine, given in [Table 1], appear ample to meet present and foreseeable requirements in all producing countries. With the occurrence of bromine salts in sea-water and other brines, the potential for bromine production is worldwide. It has been estimated that 99% of all commercially recoverable bromine is in the ocean. However, actual subterranean brines having a higher bromine content than seawater will continue to be the preferred sources of bromine for the foreseeable future. Markets and Prices About 17% (1968) of bromine produced is used in its elemental form, with the balance consumed as bromides and bromates. The largest use for bromine is ethylene dibromide which, together with tetraethyl lead, are used as an antiknock additive in gasoline. Tetra-ethyl lead is the antiknock agent. Ethylene dibromide combines with the lead after combustion in the engine to form a volatile com- pound that escapes from the engine with the exhaust gases.

Jan 1, 1975

By A. P. Anderson, J. H. Jensen, W. E. Breckoff

Bromine is the intermediate member of the halogen family of elements between iodine, a solid, and chlorine, a gas. The name is derived from the Greek "bromos," meaning stench. Bromine is the only nonmetallic element that is liquid at room temperatures with a melting point of -7.2° C and a boiling point of 58.78º C. Reddish brown in color, it dissolves easily in water to yield a red solution. Bromine volatilizes at ordinary temperatures to a red vapor that is very irritating to the eyes, nose, and throat. Density of the liquid is 3.12 and gas weighs 7.59 gpl at standard conditions. As the element is highly active, it exists in nature only as bromide compounds. Bromine was discovered by Antoine Jerome Balard in seawater bitterns in 1826 and first prepared in quantity in 1860. Distribution Bromine is widely distributed in nature and compounds occur in solution in natural brines, in seawater, saline lakes, oil and gas well brines, and in evaporite chloride minerals. The concentration of bromine salts ranges from 60-65 ppm in seawater to several thousand ppm in oil well brines and saline lakes. The distribution of bromine in marine evaporite minerals and in the solutions from which they crystallized was determined many years ago by H. E. Boeke (1908). Theoretical aspects regarding the geochemistry of bromine have been published in numerous papers (Raup and Mite, 1969). Bromine occurs in solid solution in carnallite and sylvite associated in potash deposits; in halite in salt beds; salt in oil shales; and in trona deposits. Its presence is useful as a guide in geochemical exploration. The analysis of small amounts of bromides in the presence of large amounts of chlorides is discussed by W. Schwerdtner (1963). Manganese, iron, and iodine may interfere with the determination. Other analytical methods are discussed at length in the literature (Stenger and Atchison, 1964). Sources and Reserves The sources and reserves of bromine, given in Table 1, appear ample to meet present and foreseeable requirements in all producing countries. With the occurrence of bromine salts in seawater and other brines, the potential for bromine production is worldwide. It has been estimated that 99% of all commercially recoverable bromine is in the ocean. However, actual subterranean brines having a higher bromine content than seawater will continue to be the preferred sources of bromine for the foreseeable future. [ ]

Jan 1, 1983

By Clamer, G. H.

G. H. CLAMER, * PHILADELPHIA, PA.-Unfortunately, prior to the war no serious attention was given to the conservation of tin, notwithstanding that this country is practically dependent upon outside sources for its entire tin supply. Tin is of vital importance in many industries, but it is surprising how many and how excellent are its substitutes when we become acquainted with them. Tin has always been a relatively high-priced metal, and it is part of the human attitude to associate high prices with high standards; it is not until the price of a commodity becomes well-nigh prohibitive that we hunt for substitutes, because the idea of substitution seems always to involve an assumption that the substitute must necessarily be inferior. The history of the development of bearing bronzes is a striking example of this policy. In the early clays, copper-tin alloys were almost universally used, the idea then being prevalent, which is still held by many, that a bearing to resist wear must be hard, and the harder the better. The favorite bronze bearing contained 90 per cent. copper and 10 per cent. tin; frequently, in service which was considered severe, even higher proportions of tin were used.. Such hard alloys have great resistance to compression, but as a rule they had a very wide factor of safety in this

Jan 12, 1918

By G. K. Burgess

G. K. BURGESS* and R. W. WOODWARD,? Washington, D. C.-From a metallurgical standpoint, there are several ways in which a reduction of the tin consumed in commercial non-ferrous and white-metal alloys can be effected. First, a reduction of the tin, content of the alloy; second, substitution of part or all of the tin content by some other metal; third, a substitution of a different type of alloy, which in some cases also involves a change in mechanical design. The Bureau of Standards has been studying these methods of conservation for tin alloys, particularly in regard to babbitts and bearing metals, bronzes, and solders. Much of the information secured by the Bureau was obtained from answers to questionnaires sent to manufacturers and users of these materials, so that, in general, any of the following suggestions or recommendations can be considered as being practical and as having already been thoroughly tried. Bearing Metals There is no question that the tin content of nearly all bearing metals can be reduced to some extent, and in some cases actually eliminated

Jan 12, 1918

By Wido Tilmann

13.6-1. Importance. In Germany there are large tertiary brown coal reserves, most of which are located close to the surface. Therefore, brown coal has been recovered for many years by means of opencast methods. By utilizing a high degree of technology, a rational operation has been achieved, and as a result, the mining techniques have become renowned all over the world. After the war, all the dredgers and overburden spreaders, as well as the means of conveyance, had to be redeveloped for adapting this equipment to the changing conditions of the deposits. Numerous auxiliary machines were adopted from the American earth moving industry and altered according to the different requirements. As a result of such technical developments, the output per man and per shift was increased remarkably in spite of the deterioration of the geological conditions. In the whole of Germany, the total reserves of brown coal amount to 100 billion metric tons, of which 60 billion tons are situated in the Federal Republic of Germany. In the latter area, 8.5 billion tons will be recover- able by opencast means, of which 3.5 billion tons are already developed. The annual output reached 102 million tons in 1965. This total figure comes from four different mining districts: Rhineland, Helmstedt (town at the border of the Soviet occupied zone), Hesse, and Bavaria. The production figures (1965) are as follows: [ ]

Jan 1, 1968

By WALTER B. JONES

PIG iron was first produced in Alabama in 1818 from limonite or brown ore and since then much of this ore has come from the so-called mineral district of northern Alabama, especially along the Cretaceous-Paleozoic contact. For many years the Russellville district in Franklin County, where the first blast furnace was erected, produced more than 100,000 tons of brown ore annually. Limonite has been reported at many places in the Coastal Plain region, where the formations are of Mesozoic and Cenozoic age, but these scattered deposits were never considered to be of much commercial importance. However, in the last three years a considerable quantity of this ore has been scraped up and shipped, particularly from the city of Greenville in Butler County.

Jan 1, 1938

By George Young

DURING the spring of 1910 I visited a number of open-pit brown-coal mines and underground workings in the vicinity of Halle, Halberstadt, Leipsic, Cologne and Bonn. The notes which I took and the observations which I made at the time have been condensed and make up the principal part of this paper. Certain supplementary information has been taken from several sources which are given in the paper. The mining of brown coal is one of the important industries of Germany. The coal varies in color from dark brown to almost black and is soft like loam. Pieces of wood and strips of bark and, even parts of tree trunks are frequently encountered in the excavation although the coal for the most part consists of a pulverulent, more or less matted mass of small particles of vegetal matter. It is a product between peat and lignitic coal. An analysis, taken from Coal Resources of the World shows the approximate composition of the material: Moisture, 53.73 per cent.; ash, 4.98; fixed carbon, 18.08; volatile carbon, 23.31 per cent. The principal characteristic is the amount of moisture. This seldom runs less than 48 per cent. The ash is usually low and ranges from 5 to 10 per cent. The sulphur content is usually less than 0.5 per cent. The heating effect of the fuel ranges from 2,000 to 2,500 calories.

Jan 2, 1916

EARLY this year the Board of Directors announced that, through the generous gift of past-president W. L. Saunders, a gold medal to be awarded for distinguished achievement in mining had been estab-lished. At the December meeting of the Board the medal committee reported that it recommended that the first medal be awarded to David William Brunton for "development and exposition of the principles and prac-tice of ore sampling; for systematic daily mapping of mine geology; for the Brunton mining compass; and for engineering achievements in connection with great tunnels." The formal presentation of the medal will be at the din-ner, on Feb. 16, in connec-tion with the annual meet-ing. Mr. Brunton, like several other prominent Institute members, was born in Can-ada, and came to the United States when he was twenty-four years old. He had then been in civil en-gineering work for three years and after a year more of it, deciding that mining was more attrac-tive he spent two years at the University of Michigan doing advanced work in geology a n d chemistry. His first mining engage-ment was with the Dakota and San Juan Mining Co., at Mineral Point, Ouray County, Colo. That was in June, 1875, and the young engineer had to travel 230 miles by trail from the then nearest railroad station at Pueblo. Having to come out because the company did not get in enough supplies to last through the winter he became metallurgist for the Hunt, Douglas & Stewart Co., at Georgetown, Colo. When the Hunt and Douglas plant proved a success, H. A. Taylor, the father of Mr. Brunton's later partner, Frank M. Taylor, engaged him to build the Clear Creek Reduction Works. Eighteen months later he built the Native Silver Mining Co. mill at Caribou and a year later a mill at Silver Peak, Nev., that was so successful that the principal owner shut it down to freeze out the minority stockholders. The winter of 1879 found him at Leadville where he did engineering work for the Robert E. Lee, Duncan, Wolftone, A. Y. & Minnie, and Dinero mines, eventually becoming manager of the Colonel Sellers. In 1886 he was called in on apex-side-line litigation at Aspen with the result that he went there to develop the mines for economic and legal pur-poses, and later became the manager of three of them. His most notable piece of work there was the driving of

Jan 2, 1927

By Robert R. Brookshire

Brush plating has been thought of by many as black magic bordering on alchemy. Actually it is a science that uses both electro-chemical and mechanical engineering skills and technology. We are not sure when brush plating was first used or by whom. I do know that many times when we would put in for patents on things we thought of as new and innovative, we would find that someone had done it many years before. It took World War I1 to get brush plating off and running. Now at this point, someone may be asking just what is brush plating? And why are we plating brushes? One way of describing what brush plating is, is by telling what it is not such as tankless plating. Brush plating-is an electro deposition of an electro-platable element or alloy onto a conductive surface. To do this a source of direct current is required; this can vary widely. I prefer stepless voltage control from 0-35 volts with a capacity depending on the size job to be done. This can vary up to 500 amps for normal applications. In one case we have used 7500 amps.. In the beginning a brush was actually used with a wire in the middle of the bristles and a jelly-like paste made up from tank plating solutions. The bristles were saturated with the gunk and the spot to be plated was muddled with the concoction at a potential which was the same as the applied tank Voltage. Metal was deposited but only thin coats were achieved. Today we use graphite wrapped or covered with cotton to form a Q-tip type anode. By using graphite rather than a specific metal we are able to either plate, de-plate or strip, electro- mill, electropolish, or anodize--all with the same equipment. Only the electrolyte needs to be changed.

Jan 1, 1984

Brushy Creek mine is located near the center of a linear, 40 mile long belt of mineralization that extends south from St. Joe Minerals Corp.'s Viburnum division. The mine area includes a segment of 5.4 miles long of this new mining region along which eight mines are presently operating. The geology of the area is relatively simple; the rock formations have not been disturbed through folding or extensive faulting.

Jan 7, 1973

By N. E. Cone

IT is somewhat surprising that among the many mechanical devices that were brought into the State of Colorado, that the Brückner cylinders alone have stood the test for roasting ores. The brick walls of the Arey and Stetefeld furnaces have been remodelled into reverberatories and compound reverberatories, their binding and anchor irons have been forged into hoes and shovels, while the Crosby and Thompson cylinders have been rent by the ruthless hand of the foundryman searching for a tough piece of boiler plate. Two only of these furnaces remain in operation, of the large stock that came into Colorado by car-loads several years ago, and they occupy only a subordinate position to some reverberatories on the North Boulder Creek. But to-day there are in Colorado, in active operation, ten Brückner cylinders, and two or three more running part of the time. Dur-

Jan 1, 1876

By Orson Cutler, Shepard

THE OBJECT of this paper is twofold: (1) To analyze the forces that cause air bubbles to spread on mineral surfaces in the flotation process; and (2) To develop a rational expression that will serve as a criterion of the floatability of minerals, to the end that the efficiencies of various flotation reagents can be accurately compared. Heretofore, the subject of the spreading of air bubbles has been dismissed with the statement that the surfaces of minerals on which bubbles spread are water-repellent. Imperfect understanding of the forces involved has led to the use, hitherto, of various erroneous formulas for the calculation of the comparative effectiveness of flotation reagents.

Jan 1, 1932