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Jan 1, 1913

By Thomas L. Kesler

Essentially all of the barite produced in Georgia has come from the Carters-ville district in the northwest part of the state. The earliest recorded shipment of ore, 60 tons, was made in 1894.' With the exception of the four-year period 1931 to 1934, the separate yearly output has been recorded and published since 1915, whereas the total yearly output of the United States has been published since 1880. The separately recorded production of Georgia (Cartersville) through 1947 is 2,232,544 short tons valued at $14,900,746,2 but unpublished data on the period 1931 to 1934, plus the estimated unrecorded output prior to 1915, make the actual total about 2,400,000 short tons. This is about 21 pct of the total production of the United States, which, through 1947, is 11,328,440 short tons valued at $71,683,386.2 The barite-producing part of the Cartersville district is relatively small, having from north to south a length of 4.5 miles, and a width of 2 miles. This small area, containing 35 barite mines, is the source of practically all of the barite produced in the state. The area is hilly, and has a total relief of 500 ft. The west-flowing Etowah River crosses the middle of the area, and is an unfailing source of water for operations on properties near its course. Opencut mining is carried on during the entire year, but is hampered by rain in the winter and early spring. Three railroads, two U.S. highways, and a network of graded roads provide access to and within the district, as well as excellent shipping facilities for ore and supplies. In addition to the barite, the district contains deposits of manganese, brown iron, ocher, umber, and specular hematite. Geologic Setting The area containing the barite deposits is underlain by Lower Cambrian rocks and their weathered residua. These rocks are grouped in three formations; in ascending order, these are the Weisner, the Shady, and the Rome. The Weisner formation consists mainly of finely micaceous metashale containing many random beds of quartzite, a few beds of conglomerate and metasiltstone, and beds of crystalline limestone that is apparently scarce. The formation is more than 1000 ft thick, and the base is not exposed. On account of their resistance to weathering, the rocks of the Weisner formation have sustained the higher elevations and therefore crop out on the ridges that characterize the area. Nearly all of these ridges are underlain by asymmetric anticlinal folds, and conversely the intervening valleys are underlain by synclinal folds. A diagrammatic section, showing typical mode of exposure of the Weisner rocks and their relation to overlying formations, in the limb of a fold, is shown in Fig 1. The Shady formation here consists of a lithologically distinctive series of variably siliceous specular hematite beds and thin beds of dolomite, which in places contain abundant fossils. In the zone of weathering, the dolomite has been leached and most of the hematite hydrated to ocherous and umber-ous clays, hut bedding planes in these weathered materials are commonly well preserved with or without distortion effected by slumping. This preservation of structure during weathering is lacking in the residuum that rests on the Rome dolomite, which is described below. The maximum thickness of the

Jan 1, 1950

A. MALINOVSZKY,* Belleville, Ill. (written discussion?).-I have been very much interested in Mr. Dolman's paper. We all realize, I think, that this question of developing our home industries and support-ing the new industries which have developed during the great war is very important at present. Mr. Dolman has well shown the quantity and quality of the raw magnesite in the United States, and the commercial and industrial possibility of our home magnesite and I believe, with him, that our home industries should receive adequate protection. There are two reasons, however, for believing that this may be difficult. One reason is that much American capital is invested in the Austro-Hungarian magnesite industry. The raw magnesite can be quarried and prepared for the market in Austria with much cheaper labor expense than in the United States; large deposits which are very easy to quarry and good transportation facilities also contribute to the cheapness of production. The second reason is the old saying that the magnesite found in the United States is not of the same quality as the Austro-Hungarian mag-nesite; this I doubt. Even if the magnesite found here does not in a raw state equal the Austro-Hungarian, it can be synthetized so that the finished article will have the same properties as the Austro-Hun-garian finished magnesite refractory possesses. Thaw magnesite from Greece is not the same as the. Austro-Hungarian, but it has linen demon-strated that a good refractory can be made from the Greek product.

Jan 10, 1919

(Under this heading will be published notes sent to the Secretary of the Institute by members or other persons introduced by members) Member, aged 32. Fifteen years' experience in the mining, quarrying, and manufacture of gypsum and gypsum products, as purchasing agent, designer, operating manager and managing executive. Thoroughly familiar with the business in all branches, especially the organization of efficient producing forces and machinery and the value of cost and their application to manufacturing. Desires responsible position with a financially reliable concern in the same or similar business in which an interest may be obtained at a later date. Now doing consulting work, but free for appointments after April 1. New York or Philadelphia. No. 345. Member, technical graduate. Unmarried. Aged 32. Seven and one half years' experience in mining, timbering, and mine sampling. At present, and for past two and a half years, mine sampler for well known and highly successful mining company. Desire change. Go anywhere. Prefer assisting Mining Engineer. No. 346. Member, 40 years old. 18 years' experience in examinations and operation in the United States, Mexico and South America. Especially successful with poor class of labor. Open for engagement in any part of the world, in technical, administrative or consulting work. No. 347. Member, technical graduate. Sixteen years' experience as engineer, superintendent, and manager in metal mines. Exploratory . work, developing and equipping new properties. Operation of large mines, and various systems of mining. Low costs. Specialized in iron and copper mining, but have had some experience in zinc, lead and pyrite mining. No; 348.

Jan 4, 1917

By E. E. Anderson, R. L. Newacheck, J. Kohl

Radioactive materials were used underground before the advent of the nuclear reactor. Radium containing ores have been mixed with cements and other materials for later location in oil wells by gamma ray logging since 1940.1 Perforating bullets have been marked with radium salts,, and radioactive materials have been added to drilling muds to find the cause of "lost circulation."' More recently colloidal suspensions of radioactive cobalt-60 and silver-1103 and solutions of 1-1314 have been used in waterflooding operatiorns to determine injection profiles, flow paths and water velocities. In this paper a recent and interesting underground tracer application is discussed. Development work and field engineering were carried out under the direction of Tracerlab, lnc., with assistance from personnel of the client. A gaseous tracer, argon-41, was used in an attempt to determine the cause of leakage from an underground gas storage reservoir. STATEMENT OF PROBLEM This gaseous tracer application was carried out for the Natural Gas Storage Co. of Illinois. This company has developed an underground gas storage field 1,750 ft below the surface of the earth near the village of Herscher, Ill., about 60 miles south of Chicago. The total volume of gas stored in the field was estimated to be about 13 billion cu ft in the spring of 1954. The field has a maximum estimated storage capacity of 90 billion cu ft. The gas is contained in the Galesville sandstone, previously a water bearing formation of about 25 per cent porosity. The water as it is pushed out by the gas forms a barrier for the gas around the edge of the reservoir. Over the top and beneath the bottom of the reservoir are located several layers of impervious rock, which barring cracks or unplugged and unknown wells should act as seals. Twenty-one injection and withdrawal wells were drilled into the Herscher reservoir and gas injection was begun during the summer of 1953. After a few weeks of gas injection, evidence of gas leakage was detected at the surface; water wells began bubbling and losing prime, and dry spots in the fields indicated gas leakage from uncharted oil wells. In every case, the leakage could not be traced back any further than the water bearing formations a few hundred feet below the surface. An extensive search was made to locate uncharted oil wells which were believed to be possible channels for the gas from the storage formation to the water containing formation. Long-time residents in the area assisted in the location of several abandoned oil wells. The wells when located were cleaned out and either used as vent wells to relieve the gas pressure in the water formations, or were plugged with cement. None of the wells even approached depths which would endanger the soundness of the storage reservoir. All of the injection wells were tested for leaks in the casings by conducting neutron surveys and by other techniques. To detect any leakage up through the cement-filled annulus surrounding the casing, a section of the casing wall in one well was milled out. Then, plugs were installed above and below the cut-out section and pressure applied to the annulus, which proved conclusively that the cement was sound in that well. The well was then plugged with cement and abandoned. In another well, ammonia was injected into the well and a temperature log was made. It was hoped that a leak would be re-

Jan 1, 1956

By Takeyasu Ito, Mayumi Someno, Kazuhiro Goto

SINCE the pioneering work by Kiukkola and Wagner,1 many experiments have been reported on solid electrochemistry at elevated temperatures. However, the studies have been confined to experiments under isothermal conditions. One may conceive many situations under nonisothermal conditions. With two different temperatures T1, and T2 at the two electrodes, the electromotive force, E of a Galvanic cell will be expressed by the following equation under a steady state heat transfer in solid electrolytes of zirconia-lime and thoria-lime. E = ^ $ l&-dGO2+a(T2-Ti) [1] where tO2- is the transference number of oxygen ions in the electrolyte, Go, is the chemical potential of oxygen, and a is the coefficient of the thermoelec-tromotive force due to the temperature difference. The objective of the present study was to evaluate the coefficient of the thermoelectromotive force for zirconia-lime and thoria-lime under isobaric condition. The physical meaning of this coefficient is out of the scope of the present communication. The experimental cell assembly is schematically shown in Fig. 1. The zirconia-lime electrolyte tube and thoria-lime electrolyte tube were 8.0 mm OD and 5.0 ID, from commercial sources with chemical analyses of 94.8 wt pct ZrO2, 3.85 pct CaO, 0.83 pct SiO2, 0.25 pct TiO2, and 0.05 pct Fe2O3; and 95.0 pct ThO2, 4.0 pct CaO and rare earth metal oxides, respectively. The specific gravity was 5.5 g per cu cm for zirconia-lime and 9.8 g per cu cm for thoria-lime. Original powder size before shaping and sintering the tube was several microns for both electrolytes. The distance separating the two electrodes was 4.0 or 5.0 cm. Platinum wire of 0.5 mm diam was used for the electrodes. The temperature gradient was controlled by heating one electrode with a small heating coil of nichrome wire. The temperatures at the two electrodes were measured with two calibrated Pt-13 pct Rh:Pt thermocouples, directly contacting the two platinum electrodes. The atmosphere was either air or pure oxygen. The partial pressure of oxygen in air was considered equal at the vicinities of the two electrodes, with negligibly small thermal segregation in the gas phase. The difference of the chemical potential of oxygen was controlled only by the temperature difference at the two electrodes and not by the oxygen pressure difference. The temperature ranges were 600" to 1200°C for zirconia-lime and 850" to 1200°C for thoria-lime electrolytes. Fig. 2 shows the relation of the measured electromotive force and the difference of the oxygen chemical potential at the two electrodes for zirconia-lime and thoria-lime electrolytes. The electromotive forces in the figure were measured by a *0.05 mv potentiometer. The chemical potential difference was calculated by the following equations.'

Jan 1, 1970

FRENCH steel makers are ready to support the Schuman plan. Pierre Ricard, vice-president of the French Steel Chamber syndicate, announced the industry's readiness to cooperate with the plan, which is aimed toward giving Europe an integrated steel industry. Steel men appear to have decided in favor of the plan because of its promise to unify the continent. Behind approval is the emphasis placed by French steel plant operators on continuation of the Franco Saar economic union. The French have an, abiding fear of German steel production potential. France is currently producing at an annual rate of 11 million tons, while Western Germany is producing 15.5 million tons of steel. The Saar output is placed at 3 million tons. French industrialists feel that as long as the marriage of French and Saar steel production continues, France can compete reasonably well with Germany. If Saar production should suddenly become part of the Western Germany total, it could result in an unequal competitive situation, giving Germany a production level of 18.5 million tons of steel annually, or 60 pct more than France.

Jan 1, 1952

By Lewis W. MacNaughton

The North Texas district, as herein defined, includes the counties of Archer, Baylor, Clay, Cooke, Foard, Hardeman, Knox, Montague, Wichita, and Wilbarger. This area covers generally the crest and south flank of a system of buried mountains known as the Red River uplift. The oil and gas accumulations along this feature arc in traps, which, although localized by structures incident to the regional uplift, are usually modified by stratigraphic changes in the sediments. Excepting the fields in southeastern Baylor, southern Archer, and southwestern Clay counties, all the fields within the district are on this Red River uplift. These exceptions, which have the same type of oil and gas accumulation as the other fields, are on the extreme north end of the Bend arch, which is a broad anticline plunging northward from the Llano uplift in central Texas to Archer County. The larger part of past oil and gas production has come from Pennsylvanian strata, with less important amounts from the Permian, and minor but increasingly important quantities from the Ordovician. Developments during 1939 With the later stages of development being reached in the K.M.A. field during the first half of the year, some 400 fewer producing wells were drilled in North Texas in 1939 than in 1938, when some 1750 wells were drilled. Despite this decrease in activity, production in 1939 increased about 3½ million barrels over 1938 figures, and at the end of the year the oil reserves were somewhat larger than on the first of the year. As is usually characteristic of the district, this resulted from the discovery of a large number of relatively unimportant fields. Owing principally to no appreciable abatement in wildcat drilling, more new fields and extensions to old fields were discovered this year. Although none of these discoveries was of such magnitude as to be important to the oil industry, the new developments in Montague and Cooke Counties portend greater and probably more important operations in these areas.

Jan 1, 1940

By Lewis W. MacNaughton

The North Texas district, as herein defined, includes the counties of Archer, Baylor, Clay, Cooke, Foard, Hardeman, Knox, Montague, Wichita, and Wilbarger. This area covers generally the crest and south flank of a system of buried mountains known as the Red River uplift. The oil and gas accumulations along this feature arc in traps, which, although localized by structures incident to the regional uplift, are usually modified by stratigraphic changes in the sediments. Excepting the fields in southeastern Baylor, southern Archer, and southwestern Clay counties, all the fields within the district are on this Red River uplift. These exceptions, which have the same type of oil and gas accumulation as the other fields, are on the extreme north end of the Bend arch, which is a broad anticline plunging northward from the Llano uplift in central Texas to Archer County. The larger part of past oil and gas production has come from Pennsylvanian strata, with less important amounts from the Permian, and minor but increasingly important quantities from the Ordovician. Developments during 1939 With the later stages of development being reached in the K.M.A. field during the first half of the year, some 400 fewer producing wells were drilled in North Texas in 1939 than in 1938, when some 1750 wells were drilled. Despite this decrease in activity, production in 1939 increased about 3½ million barrels over 1938 figures, and at the end of the year the oil reserves were somewhat larger than on the first of the year. As is usually characteristic of the district, this resulted from the discovery of a large number of relatively unimportant fields. Owing principally to no appreciable abatement in wildcat drilling, more new fields and extensions to old fields were discovered this year. Although none of these discoveries was of such magnitude as to be important to the oil industry, the new developments in Montague and Cooke Counties portend greater and probably more important operations in these areas.

Jan 1, 1940

By E. B. Swanson

Crude oil production in Iraq during 1932 was maintained at slightly higher levels than in 1931, but the output continued to be restricted to the requirements of local consumers. The Iraq Petroleum Co., representing British, American and French interests, which has been operating within its concession east of the Tigris River since 1926, began drilling operations on Apr. 5, 1927, and completed its first well at Baba Gurgur on Oct. 14, 1927, to which area the company has since confined its drilling activities. Relatively small quantities of oil have been produced annually, but the products have been utilized in company operations and have not been offered on the Iraq market. The Khanaqin Oil Co., which has its field of operation at Naft Khana in the so-called Transferred Territories, has been supplying the Iraq market with petroleum products from Iraq wells since March 12, 1927. The output of the Khanaqin Oil Co. refinery, at Alwand, during the past three fiscal years ending March 31, has been as follows: (In Barrels of 42 Gallons Each) 1930 1931 11931 Gasoline................................. 102,940 104,571 118,012 Kerosene................................ 104,010 108,112 111,624 Fuel oil...........................1 286,9001 332,142 354,244 503,850 544,825 583,880 The Iraq Petroleum Co. has a small topping plant, with a capacity of about 150 bbl. a day, used in the manufacture of petroleum products for the company's own needs. During the 1932 fiscal year, the production was 3918 bbl. of gasoline and 2235 bbl. of kerosene, as compared with 8157 bbl. of gasoline and 6308 bbl. of kerosene during the preceding fiscal year.

Jan 1, 1933

Committee on Reduction and Refining of Copper............ 3 A.I.M.E. Officers and Directors.................... 4 Preface. By C. R. Kuzell....................... 7 Career and Achievements of James Douglas. By Arthur L. Walker. . 9 PAPERS Smelting 1. Reverberatory Smelting Practice History of Reverberatory Smelting in Montana, 1879-1933. By Frederick Laist..............................23 Reverberatory Smelting of Raw Concentrates at the International Smelter, Miami, Arizona. By P. D. I. Honeyman (With Discussion)...... 88 Development of Gun-feed Reverberatory Furnaces at Garfield Plant of American Smelting and Refining Company. By R. A. Wagstaff (With Discussion)........................99 An Experimental Combination of Shaft Roasting and Reverberatory Smelting. By Frederick Laist and J. P. Cooper (With Discussion).... 104 Forms of Copper Found in Reverberatory Slags. By Royal B. Jackman and Carle R. Hayward (With Discussion).............111 2. Converting Practice Development of Copper Converting at Butte and Anaconda. By William Kelly and Frederick Laist...................122 Developments in Converting Lead and Copper Matte at Tooele. By B. L. Sackett.............................132 Messina Stationary Basic Copper Converter. By R. G. Knickerbocker (With Discussion)........................140 Smelting Copper Concentrates in a Converter. By George E. Beavers. 149 Sulfuric Acid from Converter Gases. By George E. Beavers......151 Development of Monolithic Tamped Periclase Converter Linings at United Verde Copper Company Smelter. By F. H. Parsons (With Discussion) . 153 3. Descriptions of Plants The Noranda Smelter. By W. B. Boggs and J. N. Anderson......165 Smelting Operations at Roan Antelope Copper Mines, Limited. By Charles R. Wraith.......................202 4. Waste-heat Boiler Practice Copper-refinery Waste-heat Boilers at Great Falls Reduction Department, Anaconda Copper Mining Company. By E. S. Bardwell......225

Jan 1, 1934

NAME AND OBJECT. SEC. 1. This Institute is incorporated under the Membership Corporation Law of the State of New York ; its corporate name is AMERICAN INSTITUTE OF MINING ENGINEERS; and its objects are such as are stated in its Certificate of Incorpora¬tion. ARTICLE II. MEMBERS. SEC. 1. The membership of the Institute shall comprise four classes, namely (1) Members ; (2) Honorary Members , (3) Associates , and (4) Honorary Associates Only Members and Associates residing within the United States of America, Republic of Mexico and Dominion of Canada shall be entitled to vote at the meetings of the Institute. SEC. 2 All Members, Honorary Members, Associates and Honorary Asso¬ciates of the American Institute of Mining Engineers as the same existed on the day of the incorporation of this Institute, are Members, Honorary Members, As¬sociates and Honorary Associates, respectively, of this Corporation SEC. 3. The following classes of persons shall be eligible for membership in the Institute, namely, as Members and Honorary Members, all professional min¬ing engineers, geologists, metallurgists or chemists, and all persons practically engaged in mining, metallurgy or metallurgical engineering ; as Associates and Honorary Associates, all persons desirous of being connected with the Institute who, in the opinion of the Council, are suitable. SEC 4. Every candidate for election as a Member or Associate of the Institute must be proposed for election by at least three Members or Associates; must be approved by the Committee on Membership, as prescribed in the By-Laws ; and .must be elected by the Council. Not less than three-fourths of the votes cast shall be necessary to an election Every person so elected shall become a Mem¬ber or Associate, as the case may be, upon payment of his first dues as herein¬after prescribed Each candidate for Honorary Member or Honorary Associate, must be recommended by at least ten Members or Associates ; must be approved by the Council ; and must be elected by ballot at a meeting of the Board of Direc¬tors by the unanimous vote of all the Directors present ; provided, however, that the number of Honorary Members and Honorary Associates shall not at any time exceed twenty SEC. 5. If any person elected a Member or Associate does not, within sixty days after notice of his election, accept the same and pay his initiation fee and dues for the current year, his election may be cancelled at the discretion of the Council.

Jan 1, 1910

By John S. Sumner

The various electrode arrangements used in induced polarization (IP) surveying can be classified according to the geometry of the electric field being measured. The simplest geometry (Wenner, Schlumberger, gradient) is the parallel or plane-wave electric field, while the three-array and pole-dipole array measure the field about a point current electrode. In the dipole-dipole array the characteristics of a dipolar field are approximately measured. The drill hole arrays employ variations of these fundamental geometries, depending on the objectives of the survey. This report compares the relative advantages and disadvantages of each of the commonly used surface and drill hole IP electrode arrays. Factors of each array that are considered are signal-to-noise ratio, EM coupling rejection, speed and cost, and resolution of polarizable bodies. It is concluded that certain arrays are better suited for different exploration objectives and for different geological conditions. Also the type and capabilities of the IP surveying equipment and method limit the choice of arrays.

Jan 1, 1973

By Martha Teach Gnudi, Cyril Stanley Smith

Jan 1, 1942

By E. J. Ripling

A NY mechanism proposed to explain hydrogen embrittlement in titanium and its alloys must, of course, be consistent with the experimental data that characterize this embrittlement. Unfortunately, however, the mechanical behavior of hydrogen-bearing titanium, at least a-ß titanium, has not been unequivocally defined. Lenning, Craighead, and Jaffee have clearly shown that hydrogen cmbrittles a-titanium by elevating its transition temperature, probably as the result of the formation of titanium hydrides. Therefore, in these alloys, hydrogen acts like at least one other interstitial contaminant, namely, nitrogen.&apos; On the other hand, ß-titanium has been shown by these same investigators to tolerate very large amounts of hydrogen without suffering severe mechanical damage.2 Mixing these two phases, however, to form the most important class of commercial alloys, the a-ß alloys, again results in severe hydrogen embrittlement, although the mechanism by which the embrittlement is produced is not of the same type as that which causes brittleness in a alloys. Ductility damage due to hydrogen increases as the strain rate is reduced in a-ß alloys, while embrittlement in a alloys increases as the strain rate is increased, since the latter is a transition temperature behavior. Steel, like the a-ß alloys, becomes more hydrogen sensitive at slow strain rates, suggesting that the mechanism producing the embrittlement in these two metals is similar. Brown and Baldwin&apos; described the hydrogen-produced ductility depression in steel as a function of testing temperature and strain rate by defining the slope of the two surfaces that produced the depression in a three dimensional chart, Fig. 1. One of these surfaces was given by the equations (de/de)4 > 0 (de/dT) < 0 [1] while the other was defined by the pair of equations Surfaces of the type given by Eq. 1 are suggested in two ways. One is an embrittlement mechanism wherein the diffusion rate of hydrogen is competitive with the rate at which the material is being deformed, as suggested by the planar pressure theory of Zapffe and his co-workers.&apos; The other is the diffusion controlled extension of Orowan&apos;s theory on delayed fracture in glass by Petch and Stables.&apos;&apos; Surfaces of the type given by Eq. 2 are also compatible with a mechanism of pressure build up in voids, according to de Kazinczy,&apos; since the solubility of hydrogen in the metal increases with testing temperature so that as the temperature is raised, the pressure in the voids is reduced. Kotfila and Erbin recently presented some data on the dependence of ductility on testing temperature and strain rate for the a-ß 3 pet Mn complex alloy at four different hydrogen levels.H Although data were presented for only three testing temperatures at three different strain rates, their results indicated that surfaces of the types defined in Eqs. 1 and 2 are produced in the alloy when the hydrogen level is sufficiently high—200 and 300 ppm—Fig. 2. Jaffee and his co-workers presented data on a number of different a-ß alloys which indicated the existence of surfaces of the type described by Eq. 2, but the ductility recovery at low temperatures as given by Eq. 1 was not found." In an attempt to aid in crystallizing this description of the ductility dependence of hydrogen-bearing a-ß alloys, tests were conducted by the author on a-ß titanium 140A with three different hydrogen contents. The tensile properties of two as-received rods and one vacuum annealed rod* were obtained over a range of testing temperatures and strain rates as shown in Figs. 3 and 4. Hydrogen analyses were made by the Battelle Memorial Institute on four pieces of the rod whose properties are shown as solid circles in Fig. 4. The hydrogen content of these pieces, taken at widely spaced intervals within the rod, were 280, 270, 289, and 270 ppm, indicating that the hydrogen content within a single as-received rod was quite uniform. One of the broken test pieces whose properties are shown in Fig. 3 as solid circles was also analyzed, and found to have a hydrogen content of 310 ppm. The analyses obtained on two of the vacuum annealed specimens were 92 and 170 ppm.

Jan 1, 1957

A visitor to the Republic of South Africa might profitably make his first sightseeing objective the Voortrekker&apos;s Monument at the administrative capital, Pretoria. Here he will find memorialized in sculptured stone the epic of the migrations of Dutch colonists from the Cape in search of new pastures and to escape British rule. He will see depicted the battles with the Bantus who were coming south also in search of habitable land, the peace treaties with great chiefs and the rise of Afrikaaner leaders. An American will be struck by similarities in events with his own history as well as in clothes and in type of covered wagons of the colonists. Before the latter half of the 19th century, little that transpired in South Africa was of any great international moment. The country had not attracted a great many settlers (about 15,000 Europeans in 1800 compared to about 2 million in the American colonies in 1776). Although some gold was being mined the majority of population was engaged in trade or subsistence farming.

Jan 12, 1962

By Allen Rogers

IT IS universal practice for corporations, at the end of the fiscal period, to call in a firm of chartered accountants to audit the books. The effect of this is to put an independent organization&apos;s seal of approval on the accounting of the business done by the management. Their report lets the stockholders know that the accounts rendered truly present the results of the year&apos;s business. This is as it should be; the average stockholder has no personal contact or even acquaintance with the managers of his enterprise and the approval of their stewardship by an indepen-dent agent is very desirable for maintaining confidence in their honesty and ability. But such an examination deals only with what may be called the arithmetic of the business; even the most elaborate audit, as the practice is at present, goes no further than to verify the items of the inventory. In other words, while checking up the entries showing the transaction&apos;s of the year and certifying to the correct-ness of the items of the balance sheet, such a report gives the stockholder no idea of the ability with which his affairs have been managed. If the profit and loss balance is satisfactory, as certified by the public accountants, he assumes that the management has been able; where it is not, he turns to the president&apos;s report and usually finds an explanation. Such an explanation never takes the form of admission of mis-takes in business judgment or of bad technical manage-ment. It could hardly be expected that it would. The stockholder is generally furnished, therefore, with a certificate of the honesty of his management, but never one of its ability. He does not worry about the latter as long as dividends come in; when they cease, his action generally finds expression in replacing the management. In other words, so long as profits are realized, he assumes the management to be good, even though its success is a matter beyond its control and better management would make larger profits. When there is no profit, the stockholders have no means of knowing whether it is due to conditions beyond the control of the management, as the annual report is sure to allege, or whether, by better management, profit is possible. Here is where the technical audit comes in.

Jan 6, 1922

By Alan D. Smith

Mine roof fall characteristics of 250 falls in 5 different room-and-pillar coal mines, located in Pike, Martin, and Floyd counties, were investigated to determine the relationship of selected parameters associated with roof failure and the assumed condition of the mine roof before failure. The selected parameters used in the study included: presence of cracks and water before the occurrence of fall, sloughing of coal ribs, floor heave condition, type of roof support (resin or mechanical anchor bolts), distance to coal face, and time of occurrence of fall after initial coal extraction. In addition, research hypotheses, utilizing multiple linear regression techniques, were generated to test the relationship among the selected parameters and mine roof condition. The results indicated that the vast majority of falls portrayed some presence of water before the actual fall, occurred in less than 30 weeks after initial coal excavation, located usually greater than 30 meters from nearest coal face, gave evidence of cracks in mine roof before occurrence of fall, generally portrayed a good roof condition before the fall, showed presence of sloughing of coal ribs, and gave no occurrence of floor heave before occurrence of fall. In terms of the characteristics of the original support systems in the mine roof falls studied, most roofs were either supported by mechanical-anchor bolts or resin or full-column bolts; very rarely did the roof appear to fail if supported by posts or cribs. A detail inspection of the hypothesis and model comparison results gave supporting evidence that the condition of the roof is not dependent on the usual indicators of potential failure, such as presence of cracks and moisture. In fact, in most cases of mine roof failure, the immediate roof condition was rated as good or better, which gives little or no indication of pending failure and collapse. Hence, a combination of factors that are not easily accessible to measurement, are the dominant factors in the determination of roof fall-potential areas.

Jan 1, 1984

STANDING COMMITTEES Executive-A. R. LEDOUX, chairman. Membership-GEORGE C. STONE, chairman. Finance-J. V. N. DORR, chairman. Library-E. GYBBON SPILSBURY, chairman. Papers and Publications-BRADLEY STOUGHTON, chairman. Nominations-Pops YEATMAN, chairman.

Jan 8, 1919

At the annual meeting of Southern California Section, held on May 28, the following officers were elected: Chairman, W. F. Staunton, vice-chairman, L. C. Mott, secretary-treasurer, A. B. Carpenter; executive committee, J. W. Neill, C. Colcock Jones, Mead Goodloe. ALVIN B. CARPENTER, Secretary-Treasurer.

Jan 8, 1919