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By Augustus Locke

Jan 1, 1923

By James T. Kemp

SOME interesting and, to American eyes, rather unusual processes for refining impure aluminum derived from scraps were found by American and British investigators who went into Germany in 1945 for the Technical Industrial Intelligence Committee Of the Joint Chiefs of Staff. What was found was recorded in a series of reports (see page 14), many of which have been released for general reading. This paper gathers under one title and summarizes the German work in refining light metal scrap. Reference must be made to the original reports for greater detail. Basically, the occasion and stimulus for the German developments in treating light metal scrap were hard necessity. Germany needed the metal for a rapacious war industry. Adequate supplies of new aluminum from reduction works were not assured. Great quantities of airplane and other light metal war scraps were forecast. It was evident that the scrap metal would have to be reabsorbed by the producing industry and would have to be kept of good quality. The normal current production of manufacturing scrap was being and could be consumed as generated. It offered no technical problem. The mixed scraps, especially those arising from crashed and decommissioned airplanes, however, presented problems of another kind. AIRPLANE SCRAP The recovery of usable aluminum alloy from the mixed assemblies that made up the piles of airplane scrap was attacked in different ways by different groups and with differing degrees of success. Three procedures actually were used On a commercial scale, one was in pilot-plant stage and another had come to a halt in the laboratory a year before Germany collapsed. Four of these five processes actually involved "refining"; that is, some measure of purification of the metal after melting. SORTING AND SEPARATION ON A SLOPING HEARTH The simplest procedure for utilizing airplane scrap involved no refining in the strict sense of the word. This was the practice adopted by two representative plants visited by the author, the Leipziger Leichtmetalle Werke, Rackwitz, Saxony, and the Vereinigte Leichtmetalle Werke, Hanover. These firms did essentially the same thing that was done in England but not with equal success, to judge by their shorter experience, the smaller tonnage handled and by the number and quality of alloys produced. The two German firms named rough-sorted scraps by their easily recognizable alloys, essentially by part and shape. They used hand labor to chop and hack and tear apart. The easily separated heavy metal and nonmetallic scraps were discarded as they were found. Steel and the higher-melting-point metal parts riveted to aluminum or built into

Jan 1, 1947

By CHARLES DORRANGE

INTRODUCTION. CULM is a general term used in the anthracite regions for many years to denote a mixture of coal, bony coal and impurities which is sent to the refuse-banks. Thus, 35 years ago culm contained the pea and buckwheat sizes of anthracite; but to-day, and as mentioned in this paper, culm is used specifically to denote the material which passes through the smallest screen in the anthracite-breaker. The smallest size of commercial anthracite is known as No. 3 buckwheat, barley, or bird's-eye coal, and is ordinarily made through a round-punched plate having openings 3/16 in. in diameter, and over a round-punched plate with opening 3/32 in. or 1/16 in. in diameter. Thus culm will consist of coal, bony coal, slate, gravel, iron pyrite, etc., ranging in size from ? 3/32 in. down to dust. Other local terms for culm are " slush," " silt," and " dirt." The first experiments towards the utilization of anthracite culm by briquetting, and the first briquetting-work done in this country, were in 1872 at Port Richmond Piers, Philadelphia, Pa., by E. F., Loiseau.1 Clay was used as a binder and the finished briquette was water-proofed with shellac, etc. Excessive cost was given as the reason for discontinuing work at this plant. The Delaware k Hudson Co., in 1876, built a plant at Rondout, N. Y., which operated until 1880. Gas-tar was used as a binder, and anthracite screenings were briquetted for engine fuel. Excessive cost, poor results in firing, and the tendency of the fuel to cut the boiler-flues were given as the reasons for discontinuing the manufacture. The next plant was built by E. F. Loiseau about 1878, at Nesquehoning, Pa., near the No. 1 or Nesquehoning colliery

Sep 1, 1911

By H. M. Howe

It has seemed to the writer that one important, and indeed sufficient reason, for our slow progress in learning the relation between the chemical composition and the physical properties of cast-iron, has been that the problem has not been attacked properly. It would be well to select the most probable working hypothesis which we can find, and proceed to test that hypothesis by comparison with observed facts, and by making new observations specially designed for such a test. Our first step, then, is to select the most probable working hypothesis ; and to attempt this selection, to state the hypothesis and its immediate corollaries, and to take some first steps toward testing it, is the object of the present paper. Its chief purpose is to bring the hypothesis to the attention of those who are more familiar with the evidence than the writer can pretend to be, and in a better position both to present new evidence and to discuss it. The hypothesis here selected is, that composition governs properties in the case of cast-iron, in the same general way and for the same reasons as in the case of steel, mutatis mutandis. This hypothesis, which of course makes no claim to originality, certainly seems reasonable and probable; its exposition and discussion are made easy by our existing knowledge of the constitution of normal or " carbon " steel; it therefore seems worthy of consideration.

Jan 1, 1902

By B. A. Stainton, John D. Gill

OUR combined economic activities have as their goal the maximum of individual well-being and national security. In this age of intense international competition the two objectives are closely related. For many decades, the maximum of well-being and ability to maintain national security have moved generally upward. The best single measure-perhaps the only adequate measure -of the level of the rising goal is the per capita real national income (national income corrected for price changes). For centuries before the industrial revolution the income of the world's population changed little from generation to generation. In our country prior to 1800 the growth of national income was hardly measurable from decade to decade. Since 1850, perhaps since the "industrial revolution," the growth of per capita real income has been increasing geometrically. Of major importance is the accelerative growth of the productive ability of our economy. Inadequate consideration of its implications is partly responsible for periodic delays in solving our princi-

Jan 1, 1946

By AIME AIME

Acid Open-Hearth Manipulation.. By ANDREW MCWILLIAM and WILLIAM H. HATFIELD, ii, 279. Discussion by J. J. MORGAN, iii, 647; E. H. SANITER, iii, 648; MCWILLIAM and HATFIELD, 111, 648. ADDICKS, LAWRENCE. The Effect of Impurities on the Electrical Conductivity of Copper, iii, 559. Address of Welcome to the U. S. National Museum, Washington, D. C. By RICHARD RATHBUN, .iv, 923. ALLDERDICE, TAYLOR. Discussion of MR. ROE'S paper, The Mann¬ facture and Characteristics of Wrought Iron, v, 1091. American Mining Engineer. Discussion by ARTHUR JARMAN, iii, 641. An Automatic Stock-Line Recorder for Iron Blast-Furnaces. By J. E. JOHNSON, JR., iii, 509. Anthracite-Washeries. By GEORGE W. HARRIS, vi, 1263.

Jan 1, 1907

By R. E. H. Pomeroy

Early in 1917, it became evident, owing to existing and pending market conditions, that a substitute for crude petroleum must be found for firing the smelter furnaces. After a review of the plants then existing, it was deemed advisable to depart from their practice and to adopt the following described system of distributing pulverized coal to the furnaces. The principal advantages of the proposed system, which influenced this decision, were: (I) Equal safety; no pulverized coal is stored at the furnaces; (2) greater ease of operation, furnace fires being controlled by regulating valves in burner branches, as in gas firing; (3) better organization; all machinery, including pulverized coal feed, is under one roof, and the organization is separate from the furnace department; (4) greater cleanliness; all machinery is under vacuum; (5) greater flexibility of application, the coal and air mixture can be piped where needcd. The design of the plant is the result of the combined efforts of the local engineering staff and of the machinery manufacturers. Many new features were embodied in this design to insure greater safety, cleanliness, and efficiency of handling. After 14 months of continuous operation, the plant has proved entirely satisfactory. The building is of structural steel, covered with corrugated steel, with many windows and is painted light gray inside and out. The building floor is of concrete with ample drains to the sewer, and the building is equipped with fire and service water piping. Fig. 1 shows the east side of the building and the incline conveyor from the raw-coal bins. The plant is operated entirely by electric power. All alternating current is 550 volts, 3-phase, 60 cycles. The pulverized-coal feeding niotors and control mechanism are operated by 220-volt direct current supplied by motor-generator sets in the building. Autamatic push-

Jan 1, 1921

By Alfred H. Brooks

The developments of the past five years have shown that Alaska, as a field for mining, stands in the first rank among the possessions of the United States. Its annual gold output is now about $8,000,000. It produces silver, copper and coal in commercial quantities and its recently discovered tin and petroleum promise to become important products. Concurrent with the gradual development of this wealth, the mining public has ceased to regard the territory simply as an arctic province where a few placer-miners struggle with adverse conditions to secure a grub-stake or a modest fortune. Of late years there has been a large influx of capital to investigate its mineral resources, but in its area of nearly 600,000 sq. miles there still remain large, unexploited and little-known fields. This work of investigation has been carried on under adverse conditions, and reflects credit on all who have shared in it, whether prospectors, mining engineers, or geologists. It is the purpose of this paper to outline briefly what has been, and is being, accomplished toward furthering the knowledge of Alaska's mineral wealth, and in this connection to present a brief history of the operations of the United States Geological Survey in the territory. A list of the publications of the Geological Survey, which pertain to Alaska, is presented as an appendix, in the hope that it may prove useful to those who are interested in the mining of this northern province. During the Russian occupation of Alaska, from 1783 to 1866, but little attempt was made to delineate its geographic features or to study its geology and mineral resources. The Russian-American Co., which long held control of the territory, was entirely absorbed in the exploitation of its fur trade,

Jan 1, 1905

By A. B. Kinzel

SILICON, unfortunately, is not in the same category as some other metals with respect to the absolute value of the highest purity material prepared. Tucker, in England, and Becket, in this country have devel-oped procedures for the purification of silicon, and Becket's process has made industrially available silicon of a purity of 99.8 per cent or better. However, even the term "silicon metal" may be a paradox to some people, although not more so than the term "amorphous" as applied to silicon. These terms come from commerce, and "metal" is used to distinguish industrially high-purity silicon from ferrosilicon, silicon-aluminum, and other high-silicon alloys. Alloys of iron and silicon with 95 per cent Si or less are known as ferrosilicon, with a designation of silicon content where necessary, and the terns "silicon metal" is invariably applied to the grades containing 96 per cent Si and higher. The Becket method of purification was referred to in a monograph on the Alloys of Iron and Silicon, and the Tucker procedure was described in some detail in that publication.1 In order to get silicon of still higher purity, a sample, prepared by the Becket method, analyzing 99.84 per cent Si, 0.020 Fe, 0.016 Al, 0.005 Ca, 0.025 C, 0.033 per cent 02, 0.006 H2, 0.006 N2, and 0.001 per cent Mn, was crushed to pass a 100-mesh sieve said further purified by a modification of Tucker's procedure. This modification differs from Tucker's method in that after treatment the 100-mesh alloy was centrifuged to remove the last traces of acid. Our directly determined analysis of this purified sample shows: Si, 99.952 per cent; Fe, 0.009; Al, 0.012; Ca, 0.003; C, 0.006; or 99.982 per cent. Silicon by difference equals 99.97 per cent. The variation between silicon by difference and silicon as directly determined is important. Although Tucker mentions the amount of insoluble matter in commercial silicon both before and after his treat-ment, he does not mention the existence of carbon in the alloy; neverthe-less, lie reports silicon by difference. Any final figure as to purity obviously results from agreement between direct determination and

Jan 1, 1939

By H. W. Hitzrot

THE new 4800-ton fine-grinding plant at the Hollinger Consolidated Gold Mines property at Timmins, in the Porcupine district of northern Ontario, went into operation in November 1937, and represents the culmination of an experimental program. The plant is a moderately low rectangular building of hollow tile on a steel frame, large enough to house four 7 by 15-ft. ball mills, with a 12 by 27-ft. classifier beside each mill. At one end is space for the addition of another mill and classifier or a mill and classifier for the regrinding of table concentrates. This regrinding is now done in the old grinding department of the main mill building. Also within the new building are the four 6-in. sand pumps for lifting the product from the low-dis- charge ball mills up to the classifier feed launders and the containers and appurtenances of a complete dust-collecting system. Together with the usual overhead crane, these constitute the major units of equipment within the new plant. The location is at the lower end of the main mill buildings toward the old tailings pond, now so neatly leveled off and sodded to rival the very best of our own W.P.A. projects. Close by the new grinding plant is a large dome-shaped structure-the new fine-ore bin designed arid built by Mr. Longmore and the Hollinger milling and engineering staffs. There are four separate automatically loaded inclined belt conveyors leading up from the bottom of the bin to the grinding plant. Each belt is equipped with a recording weightometer, in the grinding building. The whole structure and the machinery within it give the impression of permanence and a carefully integrated design with close attention to details, giving the operators every advantage for consistently good work. The many ideas and opinions behind this achievement were all ably organized and executed by the Hollinger milling and engineering staffs, anti not a few were directly initiated by them. Excellent cooperation was afforded by the Hollinger staff to the engineers helping to conduct the grinding and classification test program. It was the author's privilege

Jan 1, 1939

Professor Sir John Cadman, K. C. M. G. (1918) D. Se., F. G. S., M. Inst. C. E., was for two years Technical Adviser' of the Chemical Warfare Department and Liaison Officer between British and French Forces. The Cross of Officer of the Legion of Honor was awarded him in 1917 by the President of the French Republic "in recognition of valuable services rendered by him in the cause of the Allies." At the moment, Sir John is Director of the Petroleum Executive and Chairman of the Inter-Allied Petroleum Conference. In 1915, he was Technical Adviser of the Trench Warfare Supply Department and was awarded C.'M. G. in 1916. J. Edwards-Leckie, C. M. G., D. S. 0., went to Valcartier as second in command of the 72d Regiment, Seaforth Highlanders of Canada, with rank of Major, and later sailed for France as second in command of the unit now known as the, 16th Battalion, the Canadian Scottish. He was promoted to Lieutenat-Colonel on Aug. 14, 1915, and returned to England to take command of the 2d Canadian Reserve Training Brigade at Shornecliffe. On Jan. 2, 1916, he was promoted to Colonel. R. G. Edwards-Leckie, Lieut.-Col. of the 72d Regiment, Seaforth Highlanders of Canada (which unit later became known as the 16th Battalion, The Canadian Scottish, and under that name distinguished itself in France), left Canada for "Over There" on Sept. 14, 1914. He was promoted in France to the rank of Brigadier-General on Aug. 14, 1915, and served until severely wounded in February, 1916. He was Acting Chief of the General Staff, Canadian Overseas Forces in England from September to December, 1916. He returned to Canada in May,

Jan 8, 1918

K. Baumgarten has returned from active service in France. He reports that he saw C. W. Campbell, formerly with the 2d Engineers on the Chateau Thierry front, and believes that the latter returned to the United States on August 1. He also saw J. J. Croston; G. J. Sielaff, recently transferred to the Gas Service; Thomas M. Smither, survivor of the Tuscania after a 10-mile swim to Ireland. While in Paris he en-deavored to see Prof. Sauveur, but was unsuccessful. F. K. Borrow was given a commission as Lieutenant in the Royal Garrison Artillery in 1914, but had to relinquish it, on account of ill health, in August, 1915. His health has much improved and he hopes to resume active work toward the end of this year. Davis, A. W:, see British Columbia Engineers, below. Alfred Fox, Jr., enlisted in the Public Schools Brigade, Royal Fusiliers, in September, 1914; was gazetted Lieutenant in the Royal Field Artillery in December, 1914, promoted to Captain in November, 1915, and Adjutant to 78th Brigade, Royal Field Artillery, in January, 1916. He was appointed Staff Captain of the 12th Divisional Artillery in November, 1917. He has served continuously in France since July 1, 1915. He was awarded the Military Cross in January, 1917, and four times mentioned in despatches. E. Fraser-Campbell writes that he joined the London University 0. T. C. in January, 1918, for five weeks; enlisted with the Argyll and Sutherland Highlanders in February, 1918, and attended a training course for officer cadets at Chatham for six weeks. He was commissioned 2d Lieutenant, Royal Engineers, in April, 1918. After two months on home training at Chatham, he landed in France on June 23, 1918, posted to 180th Tunnelling Co., R. E., and is now with his unit up on the line.

Jan 10, 1918

By C. G. Rhodes, D. Kramer

The kinetics of precipitation of transient a phase during the transformation in U-16 wt pct Mo between 400° and 550°C were studied using quantitative metallography and electrica1 resistiuity measurements. The volume percent of a phase goes through a maximum in time, corresponding to a critical degree of progress of y' formation. prior to its re-solution after prolonged annealing. The fastest rate of a precipitation oc-cuvs at 500°C with a concomittant lowest peak of 9.5 vol pct a. At 450°C, 14 vol pct a, greatest fov any temperature, was observed after 24 hr witlz an associated slowest rate of formation. a precipitation at 400°C ceases after approximately 160 hr and the amount of a present remains unchanged after long times at temperature; no y' was observed metallographically at this temperature. IN the U-Mo system at 16 wt pct Mo, an ordering reaction takes place below 600°C, see Fig. 1, whereupon the random bcc solid solution, y, transforms to the ordered bct phase, y'."2 The new unit cell is constructed of three old unit cells somewhat distorted. While attempting to study the kinetics of this transformation it was observed that an unexpected phase was precipitating out early during the transformation anneal reaching appreciable amounts before disappearing after long times. The y' appeared in the presence of this new phase and after long times constituted the whole sample. Owing to the high optical activity of this unexpected phase under polarized light, it was suspected to be the a phase. Subsequent X-ray powder pictures confirmed this belief. The kinetics of a phase formation and disappearance is the subject of this paper. EXPERIMENTAL PROCEDURE A) Alloy Preparation. Alloys for this study were prepared by vacuum induction melting normal reactor grade uranium and 99.5 wt pct Mo pellets in thoria crucibles. Two ingots were prepared, and sections of the top and bottom of each ingot were chemically analyzed for uranium and molybdenum content. The results of the analyses appear in Table I. B) Metallography. Samples of 16M were wrapped in tantalum foil, sealed in evacuated (5 X 10"6 mm of Hg) quartz capisules, and annealed at 1110"C prior to being transferred directly to the transformation temperature. They were examined metallographically after increasing times to determine the progress of the transformation at 400°, 450°, 500°, and 550°C. The samples were prepared for metallographic examination by mechanical polishing with diamond paste and electrolytic polishing with a solution of glacial acetic acid and chromic acid. Since the y' phase is tetragonal, its presence can be detected by viewing the sample in polarized light. To increase the contrast between y' plates, the samples were electro-etched in a 10 pct oxalic acid solution. To reveal a phase in bright field (it can be seen in polarized light in the "as-polished" state), the samples were electro-etched in a solution of citric acid and nitric acid. To determine the vol pct a phase, a variation of the one dimensional systematic point count method as described by Hilliard and cahn3 was used. The

Jan 1, 1962

By J. N. Sicking, F. H. Brinkman

A new method for obtaining equilibrium vaporization ratios (K-values) for reservoir fluids has been developed and tested. By application of the method, complex experimental measurements of liquid and vapor phase compositions are eliminated. This simplified technique reduces the cost of experimental equilibrium-ratio data for reservoir studies of condensates and volatile crude-oil systems. The method is designed for systems of constant composition and, therefore, is best suited for depletion studies where compositional changes at high pressures are minor. The basic data required, in addition to the composition of the initial reservoir fluid, are the relative vapor-liquid volumes and densities at reservoir temperature and variom reservoir pressures. Tests demonstrated that the method predicts equilibrium ratios accurately for condensates. A single test on a crude oil was not conclusive; further testing will be necessary before the accuracy of the method can be determined for crude-oil systems. In addition to determining equilibrium ratios, the calculation method provides information on the physical properties of the "plus" component in the vapor and liquid phases. The "plus" component is that mixture of components heavier than the least volatile fraction analyzed. This information is useful in studies of both natural depletion and cycling operations for condensate reservoirs where the heptanes-plus component in the gas phase is produced from the reservoir. INTRODUCTION As more volatile oil and condensate reservoirs are found, the use of phase behavior techniques to predict their performance is increasing in importance. These techniques have long been used for condensate fields and have more recently been applied to crude-oil fields containing oils of medium-to-high volatility. In these phase behavior methods, equilibrium ratios (K-values) are used to predict compositional changes in the reservoir fluids—thereby accounting for the recoverable oil that exists in the gas phase. The reliability of the predictions depends to a large extent on the equilibrium ratios used. These values must be obtained for each component for the entire pressure range being investigated. Unfortunately, because of the complex nature of hydrocarbon mixtures, accurate K-values are hard to obtain. The equilibrium ratios for a particular component will vary not only with the temperature and pressure, but also with over-all composition of the system. The importance of composition is quite critical at elevated pressures, but becomes negligible at pressures below about 300 psia. Therefore, because most phase behavior problems involve the high-pressure region, each fluid system becomes a special case. Experimental programs to determine characteristic K-values are quite difficult and time-consuming. Thus, it is often necessary to resort to approximations of the K-value data. Charts giving K-values for various mixtures and classes of mixtures are available in the literature. However, there are two major difficulties in using them: (1) the K-values of the "plus" component (that mixture of components heavier than the last one analyzed) must be obtained by extrapolation from the K-values of the other components; and (2) the K-values obtained must finally be adjusted by trial and error to agree with observed volumetric data. To eliminate these difficulties, a new method of determining equilibrium ratios was developed. Briefly, after the composition of the system as a whole has been analyzed, the method uses empirical correlations and the gross fluid properties of the system (relative vapor-liquid volumes and densities) to calculate K-values. Because the calculative procedure is long, it is best solved on a digital computer. About one hour of machine time on an IBM 650 computer is required to develop a K-chart for the fluid being examined. DEVELOPMENT OF THE METHOD OF OBTAINING K-VALUES Equilibrium ratios are defined as the ratio of the mole fraction of a component in the vapor phase to its mole fraction in the liquid phase. This statement is expressed in Eq. 1. A typical plot of equilibrium ratios for a particular system is shown in Fig. 1. It should be noted that, at pressures near the saturation pressure, the K-values appear to converge to a common point. This apparent convergence point is called the convergence pressure and is a characteristic of the system involved. Various empirical correlations of K-values have been noted. It has been observed that an isothermal plot of

By C. S. Anderson

GEORGIA, since 1829, has produced nearly $18,000,000 from her gold mines, but in late years the output has dwindled to insignificance. In view of present universal efforts to increase gold production, it seems pertinent to record some recent observations in that field, briefly review its past and weigh probabilities of reviving gold mining there. Little in this paper can be claimed as new or original, and it does not present results of a detailed or profound investigation of the whole region. The Allatoona gold mine was reopened in January, 1932, and explored at greater depth during the period from January to June of that year. A number of other abandoned mines were visited, but since the workings, in common with most such mines in Georgia, were flooded or caved, underground conditions could not be examined. For a wider knowl-edge of the subject, a search was made through available pertinent literature and statistics, a bibliography of which is appended hereto. To all the sources obligations are gratefully acknowledged.

Jan 1, 1933

By Leo Ranney

ANY years ago a prospector came to a Nevada town and built himself a shack. Day after day he searched the hills for gold -but he found none. He closed his shack and hurried north, where a strike had been made. Next he tried to trap the flour gold that floats down the Snake River. He panned the black sands along the Oregon coast. He ranged over the mountains and up the gulches of far-off Alaska. At last, broken in health, six years ago he came back to his old home in Nevada. There his shack still stood-nobody wanted it. One day he started a garden in the rocky soil that he owned. His spade turned up a chunk of quartz, and in that quartz were stringers of gold. He had found a rich gold vein, running right under his own house. You gas producers who have hurried to Oklahoma, Louisiana, East Texas, South Texas, West Texas, even to California to drill wildcat holes a mile or two miles deep-why not, like the old gold prospector, have a look in your own back yard? Some of your coal seams contain 20,000,000 cu. ft. of natural gas per acre.

Jan 1, 1943

By K. N. Weaver

In the early 1950's the cement industry began putting a new emphasis on geology. This article points up some of the industry's raw materials problems that geologists are uniquely qualified to handle. Portland cement can be made from relatively abundant industrial minerals and rocks, and this may explain why cement producers placed little emphasis on geology during the early days of the industry. After World War 11, however, the industry began to recognize the need for geological exploration and some of the larger companies began to build a permanent geological staff. This development has its roots in: 1) The rapid expansion of the industry. After World War II and continuing into the early 1950's the demand for cement far exceeded the production capacity. This placed a great deal of pressure on the producers to enlarge capacity at their plants and to develop new sites. 2) The closing of many cement plants due to inadequate raw materials. Producers feared lack of raw materials due to inadequate exploration and evaluation. 3) An ever increasing pressure for upgrading of the quality of portland cement, necessitated upgrading the quality of raw materials. 4) The increasingly large capital investment needed to build new cement plants required a higher degree of accuracy in reserve calculation. These reasons are more or less self explanatory and will not be elaborated on. They are outlined to illustrate the probable evolution of thought among cement management to justify the development of a geological staff. In the author's personal experience the geologist must continually readjust to changing conditions within the industry. For example, cement production capacity grew so rapidly that today production is only about 70% to 75% of rated capacity (73.8% in 1963). Therefore, whereas the geologist's function during the active expansion of capacity was primarily one of exploration, one of his major functions today is the development of existing reserves. This assumes of course that reserves at existing plants have been proven to be adequate in terms of the company's reserve policy. Through the proper development of raw materials, the geologist can markedly influence quality control, production and long range planning. Examples of several of the operations of Medusa Portland Cement Co. will illustrate how proper attention to geologic detail pays off in the above areas. Because limestone is the major raw material of port-land cement, the examples will be concerned with it. DEVELOPMENT OF GEOLOGIC DETAIL One of the prime objectives of an exploration or development project should be the establishment of the stratigraphy and structure of the deposit. The basic tool for exploration and development is still the core drill, and the geologist must gain a maximum amount of information from a minimum amount of drilling. In order to obtain this objective the following is essential: 1) Adequate detailed geologic logging of cores. The core is first logged and separated into lithologically distinct units. In order to make the lithologic breaks as meaningful as possible, representative pieces of core (not all) are etched in dilute HCI. This removes the "drill polish", brings out the structure of the rock and indicates the proportion of dolomite and argillaceous material because dolomite and argillaceous material etch in relief. In this way the lithologic breaks become clearer and one gains a general idea of the chemical makeup before analysis. This method of logging lessens the probability of including two types of stone, e.g. limestone and dolomite into the same sample for chemical analysis. 2) Representative sampling for chemical analysis. After logging, the lithologic units are sampled for chemical analysis. A representative analysis can be obtained by extracting a 1-in. sample for every foot of core. For example, a lithologic interval of 10 ft to 20 ft would yield ten 1-in. samples taken at 11 ft, 12 ft, 13 ft... and 20 ft. These samples are then crushed, pulverized and split into a sample for chemical analysis. This sampling method represents a significant saving of time over splitting the entire core. 3) Preparing the core as a record. Because of the expense of storage and the difficulty of handling large amounts of core, only representative samples of each lithologic unit are saved for reference. An

Jan 1, 1965

By M. C. Flemings, F. R. Mollard

Two-phase Pb-Sn alloys, ranging in compositiotz from 12 to 26 at. pct Pb, were unidirectionally solidified in a convection-fvee system, with thermal gradients in the liquid of up to 480°C per cm. Plane front solidification Loas achieved in all alloys at sufficiently steep gradient and slow growth rate. Conditions causing breakdown of the interface to a cellular or dendritic structure were roughly as predicted by a sinlple constitutional supercooling criterion. Structures of alloys of near-eutectic composition, solidified with plane front, exhibited a lamellar structure; the alloys furthest from the eutectic exhibited a rod-like morphology. Assumptions used in a previous paper for calculations of solute redistribution in two-phase plane front growth are shown to be reasonable for Pb-Sn alloys. Results of calculations are in good agveement with experiment. These show that variations in growth rate during solidification of the composite produce marked changes in average composition of the solid. IN a previous paper, Part I,' conditions necessary for plane front solidification of two-phase alloys were discussed and calculations given on solute redistribution in this type of solidification. This paper, Part 11, describes experiments on Pb-Sn alloys, designed to check the assumptions of the analyses presented, and to demonstrate their applicability to a given alloy system (Pb-Sn). APPARATUS AND PROCEDURE General. A vertical crystal growing unit was built for the study as described below, and "normal solidification" employed throughout (i.e., the ingot was completely melted except for a portion near the bottom end and then solidification initiated). The furnace was designed to permit achieving very low interface velocities, and steep gradients, in essential absence of convection; it is sketched in Figs. 1 and 2. Simple heat flow considerations indicated choice of a small-diameter specimen (ingot) to achieve high thermal gradients; ingot size chosen was 0.3 cm in diam. The ingots were held inside silica tubes 0.06 cm wall thickness. The requirement for an essentially convection-free system was met by use of the vertical furnace with the heat source over the heat sink, as well as by use of the small diameter ingots. In addition, by selection of tin-rich Pb-Sn alloys, the diffusion boundary layer (lead-rich) was denser than the bulk liquid and would not cause convection. The only apparent driving force for convection in this system was the small transverse temperature gradient resulting from heat flow into the samples from the furnace. Such convection must have been small, however, since 1) no temperature fluctuations in the melt were noted in the recordings, which would have indicated turbulent convection, and 2) experimental results obtained and described below could not have been achieved in presence of significant convection. Ingot Preparation. Pb-Sn alloys ranging from 12 to 26 at. pct Pb were prepared from high-purity lead and tin (99.9999 pct pure metal). Each alloy was prepared by first melting the pure metals in the proper ratio in air, in a Pyrex container. The melt was then stirred thoroughly with a graphite rod and cast into a preheated graphite mold. Ingots were then prepared from these castings for use in the actual experiments; each ingot consisted of a rod of alloy, 15 cm long in a 25-cm-long transparent fused-silica tube, 0.3 cm ID and 0.06 cm wall thickness. One chromel-alumel thermocouple, made with 0.004-in.-diam wire and protected by a two-hole alumina tube, was inserted into each ingot. The 1.5 cm of the thermocouple nearest the bead were protruding from the alumina tube and were coated with a very thin layer of boron nitride paste which provided electrical insulation while allowing good heat conduction. The electrically welded junction size was about that of each wire and the cross section of the two wires represented about 0.3 pct of the sample cross section. Including the coating, the thermocouple cross section still represented less than 0.5 pct of the ingot cross

Jan 1, 1968

John M. Cairns, in an interesting letter dated June. 19, 1918, tells us of his experiences in Italy. He says, "It may interest you to know I came out to Italy after being on the Afghan frontier of Indian Baluchistan, in August last year, and for some time was posted at Turin as Railway Transport officer. At that time Turin was in the toils of the riots which were the forerunners and preliminaries which led up to the great Italian retreat (Capretto). Since then I have been all over Italy from (deleted by the censor) in Transportation intelligence, and now have just been transferred to the Directorate of Requisitions and Hirings, which now permits great opportunities of going nearly all over Italy (deleted by the censor). My address is L. of C. Branch, D. R. & H., A. P. 0. L/1, I. E. F.

Jan 9, 1918

Stanley C. Bullock, Captain, Royal Engineers, has been awarded the Military Cross. Charles L. Cantley was commissioned Lieutenant in the Fifth Royal Highlanders of Canada and went to France with the first Canadian contingent early in 1915, being Quartermaster of the Battalion. He went through the second battle of Ypres, Festubert, St. Eloi and the other engagements in which the Canadians were engaged up .to July, 1915, at which time he was promoted to the rank of Major. He was later ordered home by General Sir Sam Hughes, then Canadian Minister of War, and his services were loaned to the Nova Scotia Steel & Coal Co., suppliers of shell steel and forgers of shells in Canada. He continued with this company as chief officer in charge of munitions until the latter part of 1917, when he sailed for England with his old regiment. John D. Cooner was wounded on Apr. 9, 1918, by shrapnel, and is now in a hospital in Paris. He is getting along nicely. T. C. Gorman was killed in action in France on Mar. 18, 1918.

Jan 7, 1918