Search Documents

By Irving M. Symonds

Compania Minera de Penoles, S. A., at its Avalos unit operates a lead-zinc concentrator having a capacity of about 600 short tons per day. Lead and zinc concentrates are made by flotation methods. The concentrator is at Terminal de Provi-dencia, in the state of Zacatecas, some 70 miles south of Saltillo, Coahuila. The Penoles-Avalos railroad operating between the plant and Estacion Avalos, a distance of 6 miles, makes connections with the Coahuila and Zacatecas railroad, which in turn connects with the Nacionales de Mexico at Saltillo. The three railroads are each of different gauge, requiring the transfer of all supplies and concentrates at each junction. The mill operates on company ores, on ores from leased mines, and as a custom mill. The custom business is very small. The lead concentrates are shipped to company smelters at Monterrey, Nuevo Leon and Torreon, Coahuila. Since the European war, all zinc concentrates have been shipped to the United States. Ore Treated The major source of ore supply is a group of four mines owned or leased by the company, some three miles south of the mill in the mountains, from which the ore is delivered to the mill by a gravity aerial tramway. Custom ore comes in by rail. The ores occur in chimneys. The upper levels contained oxidized siliceous ores of lead, copper, silver and gold, with varying amounts of zinc. These ores were direct-smelted. In the first two years of operation a good deal of the tailing loss was caused by the oxidized content of the ores milled. Much of the ore in the transition zones between the oxides and sulphides was not mined. The ores now being milled are clean, hard sulphides in a limestone gangue, with only occasional contamination of oxides. The lead and zinc sulphides are of coarse structure and are freed even above flotation sizes. The galena is usually "steel" colored, easily and quickly floated. When there is any oxidation, it is usually on the coarsest crystals. The zinc minerals vary a good deal in color; a resin sphalerite predominates but there are varying shades of brown marmatites. On an average, the zinc sulphides contain 64 per cent zinc. The only common copper mineral is chalcopy-rite. Little is known of the occurrence of gold and silver. Waste minerals are mainly limestone and pyrite, both of which are barren. The ores vary from 20 to 35 per cent pyrite. Mill heads for the year 1940 and the first eight months of 1941 are given in Table I.

Jan 1, 1943

By Irving M. Symonds

Compania Minera de Penoles, S. A., at its Avalos unit operates a lead-zinc concentrator having a capacity of about 600 short tons per day. Lead and zinc concentrates are made by flotation methods. The concentrator is at Terminal de Provi-dencia, in the state of Zacatecas, some 70 miles south of Saltillo, Coahuila. The Penoles-Avalos railroad operating between the plant and Estacion Avalos, a distance of 6 miles, makes connections with the Coahuila and Zacatecas railroad, which in turn connects with the Nacionales de Mexico at Saltillo. The three railroads are each of different gauge, requiring the transfer of all supplies and concentrates at each junction. The mill operates on company ores, on ores from leased mines, and as a custom mill. The custom business is very small. The lead concentrates are shipped to company smelters at Monterrey, Nuevo Leon and Torreon, Coahuila. Since the European war, all zinc concentrates have been shipped to the United States. Ore Treated The major source of ore supply is a group of four mines owned or leased by the company, some three miles south of the mill in the mountains, from which the ore is delivered to the mill by a gravity aerial tramway. Custom ore comes in by rail. The ores occur in chimneys. The upper levels contained oxidized siliceous ores of lead, copper, silver and gold, with varying amounts of zinc. These ores were direct-smelted. In the first two years of operation a good deal of the tailing loss was caused by the oxidized content of the ores milled. Much of the ore in the transition zones between the oxides and sulphides was not mined. The ores now being milled are clean, hard sulphides in a limestone gangue, with only occasional contamination of oxides. The lead and zinc sulphides are of coarse structure and are freed even above flotation sizes. The galena is usually "steel" colored, easily and quickly floated. When there is any oxidation, it is usually on the coarsest crystals. The zinc minerals vary a good deal in color; a resin sphalerite predominates but there are varying shades of brown marmatites. On an average, the zinc sulphides contain 64 per cent zinc. The only common copper mineral is chalcopy-rite. Little is known of the occurrence of gold and silver. Waste minerals are mainly limestone and pyrite, both of which are barren. The ores vary from 20 to 35 per cent pyrite. Mill heads for the year 1940 and the first eight months of 1941 are given in Table I.

Jan 1, 1943

Both drilling and production of oil decreased in Rumania during 1935. The drilling totaled 1,042,041 ft. and production 61,973,938 bhl., being a decrease of 8.5 and 1.6 per cent, respectively. Wells completed during the year totaled 198, of which 168 were oil wells, compared with 238 and 215, respectively, of 1934. No important discovery was made during the year. The only new field found was Valea Calugareasca, where the Credit Minier completed a small well on the westward plunge of the anticline. Drilling higher on the structure will probably prove the field to be of greater importance than the results of the discovery well indicate. The only other developments of importance were the extension of the Bucsani field, the opening up of a new area on the northeast of the salt at Moreni by Credit Minier and a minor extension of the West Gura Ocnitei field. At Calinesti, on the cast extension of the Moreni field, exploration work continued and a gas well was completed, but oil in commercial quantities is yet to be found.

Jan 1, 1936

Both drilling and production of oil decreased in Rumania during 1935. The drilling totaled 1,042,041 ft. and production 61,973,938 bhl., being a decrease of 8.5 and 1.6 per cent, respectively. Wells completed during the year totaled 198, of which 168 were oil wells, compared with 238 and 215, respectively, of 1934. No important discovery was made during the year. The only new field found was Valea Calugareasca, where the Credit Minier completed a small well on the westward plunge of the anticline. Drilling higher on the structure will probably prove the field to be of greater importance than the results of the discovery well indicate. The only other developments of importance were the extension of the Bucsani field, the opening up of a new area on the northeast of the salt at Moreni by Credit Minier and a minor extension of the West Gura Ocnitei field. At Calinesti, on the cast extension of the Moreni field, exploration work continued and a gas well was completed, but oil in commercial quantities is yet to be found.

Jan 1, 1936

By L. S. Darken, H. A. Wriedt

The equilibria at 1 atm total pressure and 600° to 1300°C (1112° to 2372°F) between gas mixtures with various partial pressures of the reactive constituents (principally sulfur dioxide, carbon dioxide, water vapor, oxygen or carbon monoxide, and hydrogen) and coexisting solid phases (groups variously including calcium oxide, calcium carbonate, calcium sulfide, calcium sulfate, iron, ferrous sulfide, and the iron oxides) are examined. Tables and charts show the combinations of temperature, oxygen activity, and carbon dioxide partial pressure under which the various groups of the solid phases coexist and the corresponding sulfur dioxide pressures. In the presence of calcium sulfide, calcium sulfate, and calcium oxide, the partial pressure of sulfur dioxide has a peak value at each temperature which increases from 101 atm at about 800°C (1472°F) to 1 atm at about 1200°C (2192°F). With water vapor present, hydrogen sulfide may predominate among gaseous sulfur compounds, particularly at low temperatures and oxygen activities; under all other circumstances considered, sulfur dioxide is the dominant gaseous sulfur-bearing species.

Jan 1, 1974

By John R. Don

In the South Island of New Zealand an unusually favorable opportunity is offered for the analysis of the older crystalline rocks, underlying the sedimentary rocks which form the "country" of the gold-deposits. The Manipori formation of this island, comprising the greater part of the mountainous district west of lakes Manipori and Te Anau, in Otago, consists of an enormous thickness (estimated by Professor Hutton1 at 160,000 ft.) of crystalline schists, gneiss, syenite, and syenitic gneiss, with associated masses of granite; the whole forming the most picturesque fart of New Zealand. The famous West Coast sounds occur in this formation. No paying auriferous lodes have been discovered in it; and for this reason an examination of the rocks is specially interesting here. Stelzner, Posepny, and others, who have criticised the conclusions of Sandberger, have laid great stress on the fact that all the silicates analyzed by him were taken from the vicinity of orebodies containing those heavy metals which he notes as occurring in the silicates of the country-rock; their contention being that these metals, supposed to occur as silicates in gneiss and other crystalline rocks, were really contained as sulphides, and were therefore impregnations from the neighboring orebodies. The same objection, whatever be its weight, might be urged with equal justice against Mr. Becker's derivation of the mercury and gold of the lodes of the Pacific Coast from' the granite underlying their country-rock. In the case of the

Jan 1, 1913

By Harold V. Pearce

The plant of the Boston and Colorado Smelting Company, at Argo, Colo., has not received special notice in technical or scientific publications for some time past. Dr. Peters1 described the development of the reverberatory furnace used at Argo, but he dealt almost exclusively with the increase in size and the corresponding gain in capacity. Since the time of his description the changed conditions hare led to a modification of the

Jan 1, 1906

By Howard Scott

Invar is the preeminent low-expansion metal by virtue of the fact that it can be prepared with a zero coefficient of expansion at atmospheric temperature. This fact suggests that there is little room for improvement in the expansion properties of the low-expansion nickel steels. The inference is true, however, only so far as the expansion at and near atmospheric temperature is concerned, because the expansivity of invar starts to increase rapidly on heating above 100" C. and soon reaches the value of copper. Guillaumel met this situation by increasing the nickel content above that of invar. By that expedient, alloys having low expansivity under higher temperatures were obtained, but not without a large increase in minimum expansivity. The increase in minimum expansivity with increasing nickel content severely limits the technical applications of these alloys at high temperatures. Prospects of improving the expansion characteristics of the nickel steels is offered by alloying. Search for an advantageous alloying addition by analogy with other alloy systems, however, is not productive because the low-expansion characteristic is unique with that system. The rule of mixtures usually gives a fair value of the expansivity of other solid-solution alloys, but in the iron-nickel systems gives a value of 18 X 10-6 per deg. C. whereas the actual value is 1 X 10-6 per deg. C. Apparently suitable additions are not to be deduced from such ingenuous considerations. Recognition of the fact that the temperature range of low expansivity in nickel steels is terminated with loss of magnetism affords a more promising basis for the selection of an advantageous element. One may expect from that fact that additions of nonmagnetic elements to the iron-nickel alloys are detrimental to the low-expansion characteristic. Indeed, carbon, manganese, silicon, copper and chromium are detrimental to the expansion properties and no nonmagnetic element is reported to be beneficial. From the same viewpoint, the addition of a magnetic metal offers prospects of improvement. As two of the three ferromagnetic elements are already present in the

Jan 1, 1930

By PAUL AUDIBERT

THE downward trend of metal prices seems to act something like a reagent that precipitates selfishness in most business men's hearts; in the same way the upward trend precipitates altruism. Operators do not say: "I continue working my mine without curtailment because I can afford the present prices while my neighbor cannot and thus will give me way." They say: "I continue working my mine because 1 consider it a service for consumers. They will get better prices on a free market. Any curtail¬ment would be an attempt to raise prices artificially, that is to say, bad economics." Copper producers have learned how fallacious is such an opinion. It perhaps was not fallacious in olden times when all mines were worked on a small scale even if operating on a big deposit. At that time the supply and demand law played fair. When prices were too low and profits were vanishing for many mines, they would. shut at once, then little by little the metal scarcity would induce prices to climb up again; finally these prices would reach the point when it became profitable to again work the closed mines. Re-opening and shutting down mines was then a normal custom. Workers and operators weakly deplored this unstability, but there was nothing effective they could, do about it.

Jan 1, 1931

By George F. Learning

TOTAL DIRECT IMPACT The uranium mining industry's principal economic impacts on the Texas economy are the result of three flows of money from the industry into the remainder of the state's economy. These three are: (1) money paid to individuals (personal income) ; (2) money paid to other businesses (business income); and (3) money paid to state and local governments (government revenues). As these direct payments from the uranium industry to various other sectors of the Texas economy subsequently circulate and recirculate within the state, the indirect effects of uranium mining's direct impacts multiply to reach amounts significantly higher than the direct income flows alone. Over the past decade, the uranium mining industry has substantially increased its role as a provider of jobs, personal income, business income, and government revenues in Texas. The growth has come almost exclusively in a largely rural, seven-county area that lies within the triangle formed by the Laredo, San Antonio, and Corpus Christi metropolitan areas. The uranium mining industry, in fact, has been the major dynamic element in this rural area despite relative stagnation in most of the region's other basic economic sectors. Over the three years from 1976 to 1978, the South Texas uranium mining industry directly contributed a total of $115 million to the economy of the seven- county region in which it operated and $164 million to the economy of the entire state of Texas. In 1979 alone, the total direct contribution of the industry to the Texas economy had climbed to $124 million in personal, business, and government income. PERSONAL INCOME IMPACT In the period from 1976 through 1978, the South Texas uranium mining industry provided an average of $12.5 million in personal income each year directly to residents of Atascosa, Bee, Duval , Karnes, Live Oak, McMullen, and Webb counties -- the seven Texas' counties that make up the South Texas Uranium Belt. A1 though 84 percent of this resulted from the employment of area residents in uranium industry jobs, some amounts were also provided by the payment of rents and royalties to land owners for the use of their land and mineral rights in uranium mining operations. In 1979, the uranium industry provided approximately $38 million to residents of the Uranium Belt and the rest of Texas. This was more than double the average of $16.1 million provided to Texas residents during the 1976 to 1978 period. The full importance of the uranium industry as a source of personal income, however, should not be reckoned merely by the amount of wages and salaries that it pays directly to its own employees, nor by its rent and royalty payments paid directly to land and mineral rights owners living in Texas. The added payments that the industry makes directly to other Texas businesses and state and local governments in Texas are themselves converted into personal income as those business firms and government units in turn pay their employees. All of the direct income payments made by the uranium industry circulate and recirculate within the state's economy, multiplying their impact as they go, until they eventually all leak out of the state as federal taxes or as payments to individuals or businesses located outside of Texas. The combined circulation and recirculation of the direct personal, business, and government income that was provided by the-uranium industry in Texas during 1976, 1977, and 1978 resulted in an average annual amount of indirect personal income of more than $83 mill ion. This alone was $20 mill ion more than the industry's average annual sales during the same years. The total of combined direct and indirect personal income contributed to the Texas economy by the uranium mining industry in that same three-year period thus averaged almost $100 million annually. In 1979, the amount of indirect personal income contributed to the Texas economy by the circulation of uranium mining's direct contributions had risen to about $196 million, more than double the average of the previous three years. The combined direct and in- direct personal income impact in 1979 thus amounted to $234 million. BUSINESS INCOME IMPACT The income provided directly to other Texas business firms through the purchase of needed goods and services by the uranium industry has been twice as big as the industry's payrolls. In 1976, 1977, and 1978, the South Texas uranium industry spent an average of almost $36 million each year to buy both goods and services from other Texas businesses. By 1979, this direct contribution to the Texas economy had swollen to $76 million. The biggest share of the uranium industry's payments to other businesses have gone to contracting firms, including both construction firms and those providing specialized mining services. In the past four years, about 40 percent of the direct payments made by Texas uranium producers to other Texas firms have been to contractors. Texas wholesale and retail firms have also shared in the business sales provided by the South Texas uranium mining industry. Over the past four years, Texas wholesale and retail trade businesses have accounted for about 34 percent of the uranium mining industry's purchases from other Texas businesses. Public utilities firms have received another six per- cent, while Texas manufacturers and transportation firms have accounted for about five percent each. The other sectors of the state's economy, including other mineral industries, agriculture, finance, insurance, real estate, and services, have accounted

Jan 1, 1980

By E. S. Moore

THE Kolar gold field has been for a long time the most important gold-producing area of India. It is situated in the State of Mysore, southern India, and not far from the City of Bangalore. The productive field is about 3 miles long and in it a gold-bearing quartz vein varying in width from 1 in. to over 10 ft. is worked. The vein carries high values to great depths and many of the mines have paid large dividends. GEOLOGICAL FORMATIONS IN THE MOLAR REGION The rocks of the Molar region are pre-Cambrian in age and bear a close resemblance to some of the pre-Cambrian formations of America. The oldest rocks seen are basic lavas, now mostly altered to hornblende-schists, with which is associated some banded iron-formation; these rocks are similar to the Keewatin schists and iron-formation in the Lake Superior region. The schist is cut by the gold-bearing quartz vein. In certain parts of the area there is also a conglomerate containing pebbles of granite, jasper,, and schist. The matrix resembles a horn-blende-schist and is intruded by small granite dikes, which in some cases have been pinched off by squeezing of the rock. This has led Dr. W. H. Smeeth, Chief Inspector of Mines of Mysore, to whom the writer is greatly indebted for information regarding this area and for his hospi-tality while visiting the field, to regard this conglomerate as a breccia due to crushing of granite dikes in the schist. Dr. J. W. Evans has regarded the conglomerate as probably a squeezed glacial boulder clay. From analogy with pre-Cambrian conglomerates in America, the writer regards it as a metamorphosed rock similar to our basal Huronian conglomerate. However, the main bearing which it has upon the problem under discussion is the apparent fact that it is younger than the schist

Jan 3, 1918

By Irving M. Symonds

COMPA[N]IA Minera de Penoles, S. A., at its Avalos unit operates a lead-zinc concentrator having a capacity of about 600 short tons per day. Lead and zinc concentrates are made by flotation methods. The concentrator is at Terminal de Providencia, in the state of Zacatecas, some 70 miles south of Saltillo, Coahuila. The Pe[n]oles-Avalos railroad operating between the plant and Estacion Avalos, a distance of 6 miles, makes connections with the Coahuila and Zacatecas railroad, which in turn connects with the Nacionales de Mexico at Saltillo. The three railroads are each of different gauge, requiring the transfer of all supplies and concentrates at each junction. The mill operates on company ores, on ores from leased mines, and as a custom mill. The custom business is very small. The lead concentrates are shipped to company smelters at Monterrey, Nuevo Leon and Torréon, Coahuila. Since the European war, all zinc concentrates have been shipped to the United States. ORE TREATED The major source of ore supply is a group of four mines owned or leased by the company, some three miles south of the mill in the mountains, from which the ore is delivered to the mill by a gravity aerial tramway. Custom ore comes in by rail. The ores occur in chimneys. The upper levels contained oxidized siliceous ores of lead, copper, silver and gold, with varying amounts of zinc. These ores were direct-smelted. In the first two years of operation a good deal of the tailing loss was caused by the oxidized content of the ores milled. Much of the ore in the transition zones between the oxides and sulphides was not mined. The ores now being milled are clean, hard sulphides in a limestone gangue, with only occasional contamination of oxides. The lead and zinc sulphides are of coarse structure and are freed even above flotation sizes. The galena is usually "steel" colored, easily and quickly floated. When there is any oxidation, it is usually on the coarsest crystals. The zinc minerals vary a good deal in color; a resin sphalerite predominates but there are varying shades of brown marmatites. On an average, the zinc sulphides contain 64 per cent zinc. The only common copper mineral is chalcopyrite. Little is known of the occurrence of gold and silver. Waste minerals are mainly limestone and pyrite, both of which are barren. The ores vary from 20 to 35 per cent pyrite. Mill heads for the year 1940 and the first eight months of 1941 are given in Table I. [ ]

Jan 1, 1942

By J. D. Price, W. M. Bertholf

A. C. RICHARDSON*—First of all, [ think that the paper represents a lot more work, study, and correlation than has been indicated by the brief talk by Mr. Price. I like the way he started out and described the areas from which the samples were obtained, the locations of the washing plants, the available tonnages, and other background information with which to evaluate the data he submitted later on. Then I like the way in which he described the various types of washing plants, the tonnages handled and the difficulties of the washing problems; showing the amount of material that lies close to the specific gravity at which the washing separation is made. Later he gave figures from washing plant operations showing recoveries and cleaning efficiencies. He then discussed his own plant at Pueblo. It is the same old plant, I think, that I worked around a good many years ago. It is unusual to find a plant treating nearly 5000 tons of coal a day on tables. But this table plant is, I believe, more efficient than is indicated by the figures that Mr. Price gave. To determine the efficiency of a cleaning operation or to compare it with another it is necessary to consider the quantity and character of the material close to the specific gravity at which the separation is made. It is not fair, I believe, to penalize the table operation by something like 4 pct of out-of-place-material as he has done here. The variety and difficulty of the coals that he has to wash, the continuous shift and change in their composition make a very difficult cleaning problem and the table performance is excellent. I believe that the information in this paper will be of interest and value to anyone operating or planning to build a coal cleaning plant in this or other areas; particularly where the cleaning of fine coal is a problem. The data may be used for comparative purposes in determining the relative efficiencies of other cleaning plant separations. E. D. HAIGLER*—What is a Baum jig? J. D. PRICE (authors' reply)—A Baum-type jig is one in which the pulsations of the water is secured by means of a pulsating air current applied on top of the water. I imagine you are all familiar with the old plunger-type jig which is in effect a U tube in which a plunger on one side of the U, moving up and down, causes a corresponding pulsation on the far side of the jig. In the Baum jig, the pulsating air current is applied on the surface of the water on one side of the U tube of the jig and gives a corresponding pulsation on the other. It is also commonly known as a pneumatic jig. The control of the rise and fall of the water in the jig body proper is under much better control than it is in any of the other type jigs. Mr. Richardson could enlarge on that feature, for I know that he has had considerable experience with these jigs. A. C. RICHARDSON—You have asked how to control a Baum-type jig. The pulsations in a Baum jig can be modified and regulated to a marked degree by the amount of water admitted to the jig and by the adjustments of the valve which regulates the manner in which air is admitted. The number of pulsations per minute is controlled by the number of cycles of the air valve. Thirty to forty cycles per minute is a good speed for large jigs treating coarse sizes of cod. With an air valve it is possible to modify the time-velocity curve of the pulsating water to some extent which in turn determines the action in a jig bed. Within limits the following parts of the air valve cycle may be regulated: (1) the rate and period of air admission, (2) the period of air expansion, (3) the rate and period of air exhaust, and (4) the period of air compression. The rate and period of air admission determines the acceleration of the water at the beginning of the pulsion stroke and the amplitude of the stroke. The period of air expansion, after inlet port is closed, is one in which the water has reached the desired velocity, positive acceleration reduced, and the bed held in a mobile condition. The rate and period of the air exhaust can be adjusted to modify the degree of suction and so modify the manner in which the particles in the bed stratify. The compression period, alter the exhaust port closes and before the intake port opens may be used to advantage in retarding the downward velocity of water during the suction stroke. An ideal jig stroke is one in which during the up stroke the bed is lifted slowly in a mass and opens up like an accordian with the bottom layers dropping away first. With the bed open and mobile the particles adjust themselves according to their hindered settling rates. During the down stroke, while the bed is still open the particles of high specific gravity are accelerated toward the bottom layers. It is possible to approach this stroke with all types of jigs but it is less difficult to approximate it with a Baum jig.

Jan 1, 1950

By John Marshall

THE purpose of this paper is to present to the profession data and experience obtained over a period of 5 years in the operation of 87 shaker-conveyor units, and the production of 2,169,638 tons of run-of-mine anthracite coal. The data are not generally available and should be of interest to those concerned with the operation of anthracite and bitu-minous mines. To simplify comparison, a ton of 2000 lb. of raw run-of-mine coal has been used as the production unit throughout this paper.

Jan 1, 1940

By Fortunato Pereira Gamba

The Department of Narino (formerly included in the Department of Cauca) is a narrow band about 170 km. (100 miles) wide in the southern part of the Republic of Colombia, near the boundary of Ecuador, as showu in the sketch-map, Fig. 1. Its capital is Pasto, a small city of 25,000 inhabitants; the pri~icipal towns are T?querres, Cumbal, Ypiales, Barbacoas, and Tumaco. The port on the Pacific ocean is Tumaco, and traffic in the interior is carried partly on the Patia river (steam navigation to the fluvial port of Barbacoas), and afterwards overland over poor roads by human bearers or on mule-back.

Jan 1, 1913

US 4,183,794 - Electrowinning zinc from a zinc sulfate solution produced by leaching zinc ore with sulfuric acid. The leach liquor is subjected to electrolysis in a first cell having an insoluble anode to deposit primary zinc on the common electrode. The coated electrode is transferred to a second cell having an alkaline electrolyte, and electrolysis is effected in the second cell to transfer zinc from the common electrode to the second cell cathode in a spongelike form which is readily stripped. R.H.C.L. Ross. Jan 15, 1980. 10 pp. (204-119). Filed: 12-22-77 (863,190). Same: Canadian 1,051,820, dated Apr. 3, 1979.

Jan 1, 1982

By G. C. Stone

IN common with many members of the Institute, I was much interested in Mr. Kent's paper on " Manganese Determinations in Steel," * read at the Virginia meeting. Having recently had an opportunity to collect a similar series of results for spiegel, I venture to offer them to the Institute, hoping that they may also prove of interest. Sample No. 1 was taken at our works, where the spiegel was made,

Jan 1, 1883

Article IX of the Bylaws constitutes the basic instructions to the Nominating Committee The first duty of the Nominating Committee is to select a candidate for Director and President-elect It is desirable that the successive Presidents from year to year be men of differing professional interests so selected that over a period of years each major group in the Institute will be represented in the Presidency a number of times bearing some reasonable relationship to the numerical strength of that group in the Institute In Section 2 of Article IX it is stated that "a sufficient number of Directors be selected on the basis of geographical districts so that each district will have at least one representative" These districts, as now established, are shown in the accompanying map There are ten districts including the New York metropolitan district Each of these districts is entitled to one Director, except the metropolitan district which is entitled to six Each year each district, the term of whose officially recommended Director expires, shall suggest a candidate and if desired an alternate candidate to the Nominating Committee to fill the vacancy If a candidate and an alternate are suggested they should preferably have different Divisional or Branch affiliations The Chairmen of the Sections In the district shall constitute a committee to select the candidate or candidates The Sections shall rotate the chairmanship, as shown in the Appendix to this instruction It is desirable that in filling a quota vacancy in any district, the selection be made from the name or names suggested by the district

Jan 1, 1952

By S. Robinson Brainard

In 1957 the pay of chief executives in the nonferrous metals industry was well above average when compared with other major industries. Furthermore, it continued to rise last year while sales declined 8.2 pct and profits plummeted 32.7 pct on the average. Compensation of Chief Executives: One of the primary objectives of the survey is to measure year-to-year changes in top-management total compensation as it relates to company size and industry characteristics. Total compensation includes salary, bonuses, and the value of deferred contingent compensation awards.

Jan 10, 1958

By H. M. Howe, E. C. Groesbeck

That the quiescence of a liquid while it is solidifying should favor the formation of columnar crystals, normal of the cooling surface, is seen readily on considering the mechanism of solidification. First, each particle of any composite liquid, whether it be an aqueous solution or a molten metal, in solidifying splits up into two parts, different in composition and hence in fusibility. One part is infusible at the existing temperature, and hence solidifies, and in general attaches itself to the inclosing walls of metal which have already solidified; A, Fig. 1. The other part is fusible at the existing temperature and hence remains molten. In the case of carbon steel, the part of each drop which actually solidifies is poorer in carbon than the drop itself was before it began to solidify, and this impoverishment of the solidifying half-drop enriches the other half-drop in carbon, and thus makes it unfreezable at the existing tern- By this mechanism there arises during solidification a "littoral" or shore layer of liquid B, Fig. 1, bathing the already solidified walls, and more fusible than either those walls or the great remaining central mass of liquid or " deep sea " C, from which it separates them. It is essential that we grasp clearly this conception of a fusible littoral molten layer coating the already solidified walls and separating them from the deep sea. Meanwhile heat is flowing rapidly outward through these walls, its escape cooling them, so that if any given particle of the deep sea metal could get past this littoral layer and come into contact with the solid walls, it would in turn solidify, and like its predecessors would split up in solidifying into a less fusible half-drop which would attach itself to those . walls and a more fusible one which would remain molten. Thus we see

Jan 1, 1920