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By J. J. Donos

IN the operation of a smelter, continuous and accurate determination of smoke losses is essential for purposes of metals inventories and as a check on the efficiency of smoke recovery apparatus. Previous to the development of a continuous and automatic smoke sampler by R. MacMichael, in 1924, two methods were in vogue, and still are in some smelters, for measuring solids passing out of a flue or stack. These are: (1) the so-called dust concentration method whereby the gas volume passing through the flue is first measured and then the total amount of solids carried in the smoke stream calculated from the weight of suspended matter filtered out of a measured volume of gas; (2) the balanced tube method is independent of gas volume flowing through the flue, and relies for its accuracy on the fact that a true smoke sample may be taken if the velocity of the gas in the sampling tube is constantly maintained at a known ratio of the average flue gas velocity. The total amount of solids passing through the flue is then proportional to the weight of filtered solids and to the ratio of the area of the flue to the area of the sampling tube, corrected for the velocity ratio. The limitations of the first method lie in the uncertainty of the varying volume of gas arising from metallurgical operations and the unreliability of ordinary gas meters to hold their accuracy under

Jan 1, 1951

By C. N. Reid

In the course of annealing studies on molybdenum, it has been observed that a carbide precipitates preferentially on internal and external surfaces. The evidence for this is as follows. Electropolished bend specimens prepared from two grades of commercial molybdenum were loaded in a closed but unsealed tantalum can, and were annealed for 1 hr at 2000°C under a vacuum of 1 x 10-4 torr. The compositions of these materials are summarized in Table I. The samples were then slowly cooled at an average rate of 10°C per min, and were examined when cool. The surfaces of specimens prepared from Molybdenum A were consis- tently clean and featureless, except for thermally etched grain boundaries, see Fig, l(a). On the other hand, Molybdenum B had surfaces containing many needle- and featherlike markings, see Fig. l(b). These features were present in all surface grains, and within a given grain belonged to families

Jan 1, 1965

I strongly endorse Mr. Jackson's (Inland Steel Company) oral comment on the authors' paper that, as blast furnace slag is removed from the BOF charge, lime solution may be retarded. After two or three pourings, the blast furnace slag will contain some iron oxide and considerable manganese oxide, and it is hot and possibly still liquid. A few thousand pounds of this slag will speed up the slag development rate considerably and could be considered a good auxiliary flux. Although the removal of blast furnace slag from the BOF charge lowers the total sulfur load by 40 to 50%, we must have a good, quick slag development in the BOF to bring .030 to .035% sulfur hot metal to .020%, a requirement on a high percentage of our steels today. In discussions at off-the-record meetings and one not published at last year's annual meeting as well as discussions with many operators over the past 1-1/2 years, I predicted that the removal of blast furnace slag could slow down lime dissolution and that, if a shop had dissolution problems before, the problem could be quite serious.

Jan 1, 1972

By L. G. Truby

DISCUSSION By Rhrt G. Nisle, Phillips Petroleum Co., Barthesville, Okla. The subject paper presents the results of a reservoir behavior analyzer study of the pressure-production performance of five Ellenburger pools in West Texas. These five pools are Wheeler, TXL, Andector, Embar, and Martin. This laboratory has also made reservoir behavior analyzer studies in this area and arrived at substantially the same conclusions. Although the principal results of the studies made in this laboratory are confirmed by the results in the subject paper, there are certain points of difference. The points of difference are (1) the subject paper includes the Martin pool in the common aquifer, whereas our studies indicate that it is not, and (2) the subject paper concludes that the effective aquifer is considerably smaller than that derived from studies made in this laboratory. In terms of reservoir analyzer data, our rejection of Martin is based on the inability to obtain a satisfactory match of the pressure curve when Martin is considered as lying within the common aquifer. A satisfactory match was possible, however, when Martin was run as an isolated pool. This indicates that the pressure disturbance resulting from production at Martin had not reached Embar, Andector, TXL, or Wheeler at the time of our study. A similar situation exists relative to Dollarhide. In tern of geological data, our rejection of Martin is based on the presence of a faulted zone between Martin and Embar. This condition is indicated in Fig. 4 and again in Fig. 10 of the subject report. If a permeable connection between Martin and the other fields does exist, it is probably by way of a detour around this fault. The second point of difference between the two studies is illustrated by a comparison of Fig. 4 of the subject paper with Eg. A. Fig. A is obtained from an internal report on one of the studies made by this laboratory. It will be noted that the area indicated in Fig. 4 is roughly that marked "Pool Unit" in Fig. A. The additional portion of the aquifer shown in Fig. A was simulated on the reservoir analyzer by means of the water drive network. A satisfactory pressure match could not be obtained without this additional network. The differences involved here stem from a more fundamental consideration concerning reservoir analyzer operating techniques. The true source of these differences in reported results cannot at this time be determined because of the incompleteness of the subject paper. It is not stated, for instance, whether the pressure match was induced by altering the field resistance or the field capacitance, or both. Changing analyzer

Jan 1, 1953

By R. E. Head

SOME mixtures of sulphide and oxide ores from the Tintic district in Utah are of a sufficiently good grade to be shipped to the smelter without beneficiation. In mining this type of ore, however, a material tonnage of ore of a similar composition but of lower grade is obtained. It is a ques-tion of economics whether such ore should be shipped with a certainty of a small return or concentrated if that would yield a sufficiently increased return to amortize plant construction and upkeep and yield a higher rate of profit than at present. It may be assumed that the tonnage of this borderline ore is constantly increasing and that eventually it will, attain such proportions as to justify plans for milling on a relatively large scale. Under existing conditions, the producer of mixed sulphide and oxide ores is not greatly concerned about the physical characteristics of his ore or of its mineralogical complexities, since his contract with the smelter calls for payment on the basis of chemical analysis. When concentration is contemplated an entirely different picture is presented. Percentages of valuable metal content must then be con-sidered in terms of minerals, for it is in the form of minerals that recoveries are made and losses sustained. In describing the performance of a given flotation mill and reagent combination, it may be stated as a generality that a specific percentage recovery of valuable elements is made. Tech-nically, however, the concentrator is really constructed and the reagents are selected to recover the valuable minerals. These considerations must be given prominence in discussing border-line ores from the Tintic district because of their physical characteristics and mineralogical composition. Because of these peculiarities they may be justly termed complex, since their lead, silver, and copper contents are each represented by two or more minerals of different chemical composi-tion and presenting widely divergent physical properties. This paper sets forth the results of a microscopic study of a type of borderline ore from the Tintic district that is now being treated by direct smelting. A

Jan 1, 1938

By W. B. Lewis, M. E. True, M. C. Leverett

Tars paper states the theory underlying the design of two kinds of dimensionally scaled models of parts of idealized oil fields. One of these simulates an oil well and its surrounding sand for a distance of 16 ft. radially from the well. The other model simulates linear flow through layered sands. Construction and operation of the models are described and typical data are given. The unique features in the design of the models are: (I) the treatment of the permeability-viscosity quotient as a single variable and (2) the use of previously reported experimentally developed relations between relative permeability and saturation and capillary pressure, saturation, porosity, perm ability and interfacial tension. The models at present simulate flow of oil and water only, through unconsolidated sands. They are superior to unscaled models, which may give rise to erroneous conclusions. The models are designed to study the desirability of various methods of sell completion and the effects of various factors on recovery of oil from layered sands.

Jan 1, 1942

By Tadao Nagai, Masao Sato

Electrochemical measurements have been carried out in an auto- clave to investigate the electrochemistry of hydrogen precipitation of nickel from acetate buffered solution. After having previously obtained the rate equation for this reaction we have now made a concentrated effort to explain the rate equation electrochemically. A saturated NaC1-type Ag/AgC1 reference electrode has been improved so that it can be used in an autoclave. Polarization curves for the reaction, [H2=2H+ + 2e,] on nickel electrode were measured in solutions free from nickel ions at 185°C, and the parallel curves were obtained by changing PH2 and pH for normal and reverse reactions, respectively. Polarization curves in nickel solutions were complex, probably because the potential of hydrogen electrode is close to that of nickel and of the nickel surface altered during polarization. Then the nickel electrode potential and the reaction rate were measured simultaneously during pressure reduction at various hydrogen pressures and at various nickel concentrations. The reaction rates in terms of current density were plotted to obtain the local polarization curves for reactions Ni2+ + 2e ? Ni and H2 ?2H+ + 2e. The anodic and cathodic local polarization curves exhibit potential dependency. Therefore it is likely that the pres- sure reduction can be regarded as a coupled electrodes reaction.

Jan 1, 1973

By S. B. Lement

THE nature of the carbides that form during the tempering of martensite is a subject of continuing controversy. The only direct methods of identification available are X-ray and electron diffraction. These methods are subject to several difficulties. Only a relatively few diffraction lines of appreciable intensity emanate from carbide phases that are formed at low tempering temperatures. Furthermore, some overlapping of carbide and matrix lines occurs. There is also the problem that numerous lines in the patterns of possible carbide phases that may be present have about the same d-spacings. Increasing the number of carbide lines and eliminating the matrix lines can be accomplished by extraction techniques. However, there is always the possibility that a change in carbide structure will occur as a result of removal from the parent matrix. Therefore, such techniques as electrolytic extraction and making extraction replicas should be checked by other methods. For identifying small amounts of carbide in a tempered martensitic matrix, electron diffraction carried out in reflection is more advantageous than X-ray diffraction. To properly prepare a specimen for reflection electron diffraction, an etchant that will selectively attack the matrix and thereby cause the carbide particles to stand in relief should be used. With an electron beam directed at a grazing angle to the specimen surface, the major contribution

Jan 1, 1960

R. B. BRINSMADE, Ixmiquilpan, Hgo, Mexico* (written discussion). As the discussion of Mr. Graton's paper by Messrs. Norris, Patterson, and Crane has been from the standpoint of the mineral land-value owners, a few remarks in the interest of the "under dog"-the average taxpayer and citizen-may prove timely. In my discussion of Doctor Raymond's Paper1 and of the papers of Messrs. Gibson2 and Godson, 3 have endeavored to demonstrate, from both political economy and history, that our existing system of unrestricted private ownership of land is incompatible with equality of economic opportunity and, therefore, subversive of our democratic political institutions. In Mr. Graton's paper, the same land problem is important, though camouflaged by the failure of the Federal income tax laws to distinguish between land and capital, in the requirements for valuation, or between earned and unearned incomes in the levying of taxes. I disagree with Mr. Graton's statement, on p. 2967, as follows: The immense majority of mining ventures are failures. A multitude of disappointments is relieved by occasional success. Were it not for the chance of great rewards, all the vitally necessary but mainly unremunerative work of exploration would not be undertaken. In contrast with nearly all other fields of endeavor, it is altogether unlikely that, on the whole, the gains in the successful mining ventures suffice to offset the losses in the unsuccessful.

Jan 3, 1920

By W. W. Wen, S. C. Sun

The objective of this investigation was to study the electrokinetic behavior of oxidized coals to indicate the feasibility of separating oxidized coals from ash materials and pyrite by an amine flotation process. The effects of soluble inorganic electrolyte products from coal oxidation were also examined. The electro-kinetic behavior of coals of different rank and degree of oxidation were studied by an electro-phoreses technique. Generally, increasing the oxidation increases the negative value of the zeta-potential and decreases the isoelectric point (IEP). Flotation results indicate that the flotation recovery increases with decreasing pH values, and that with ferrous sulfate at pH 6.5 the flotation recovery is optimum while the pyrite is depressed. Comparing the flotation results with the electokinetic results verified that in the presence of ferrous sulfate, the maximum hydro-phobicity of oxidized coal with dodecylamine and frother is near its IEP, which is around pH 6.5 to 7.0.

Jan 1, 1978

By James Norman, E. W. Gieseke

SPODUMENE is a lithium-bearing pyroxene, and is an important source of lithium compounds. Because of its high alumina and lithia content. it might be a desirable constituent of glass batches. The use of spodumene in ceramics will undoubtedly increase, as it has been shown that a mixture of the proper proportions of this mineral with soda feldspar and potash feldspar has a much lower maturing temperature upon firing than has any one of the three components.1 The mineral spodumene seldom occurs as pure mineral, but ordinarily with feldspars, mica and quartz. All spodumene-bearing rocks tested contained these minerals as gangue. Small amounts of iron and manganese oxides also were present, usually as stains on the silicate grains. Mica associated with the spodumene carried a considerable amount of lithia. This was discovered in flotation tailings, which, although virtually free of spodumene grains when examined microscopically, showed 0.4 to 0.5 per cent Li20 on chemical analysis. The lithia content of micas picked from the North Carolina spodumene rock was variable. Some samples contained little lithia, others more than 3 per cent. In 1938, under the supervision of Oliver C. Ralston, [t] the Bureau of Mines, in cooperation with the Tennessee Mineral Products Corporation, undertook to study the beneficiation of North Carolina spodumene by froth flotation. The Bureau had previously published investigations on the beneficiation of spodumene.2, 3 The methods described in the second publication3 did not give good results with badly weathered spodumene rock, so that more thorough investigation of the subject was warranted. STUDY OF METHOD OF FLOTATION SEPARATION Most of the work on concentration of spodumene was done with rock from near King's Mountain, North Carolina. Rock from two

Jan 1, 1940

By A. B. Young

IT is the he object of this paper to describe a Cottrell treater that was placed in operation, in April, 1919, at the Tooele plant of the International Smelting Co., for the purpose of recovering solids from the gases from the McDougall roasting furnaces. Fundamentally, the treater is simply a flue containing rows of vertical plates, forming the grounded electrode, alternated with rows of small horizontal pipes, forming the negative electrode, with proper provision underneath for taking away collected dust. There are advantages in construction over the more cumbersome types, both the vertical-tube and the vertical-box, particularly in the elimination of heavy supporting columns and massive foundations, giving a much lower first cost. There are no right-angle turns to interfere with gas distribution; consequently there is greater efficiency, or, in other words, a greater volume of gas per minute can be effectively treated. Another advantage of the horizontal installation over the vertical is that the principle of the selective precipitation of the various components of the dust and fume as they pass along the electric field may be utilized. Since the treater has been placed in operation, the results have been quite satisfactory and, in many ways, particularly in regard to the volume of gas that may be treated, have greatly exceeded expectations.

Jan 8, 1920

By T. Sterry Hunt

AT the meeting of the Institute in Easton, October, 1873, I made a communication on the Ore Knob copper mine, in Ashe County, North Carolina (Transactions, vol. ii, p. 123), in which I called attention to the chemical decomposition alike of the pyritous lode and the inclosing gneiss rock to a depth of 60 feet, by which the feldspar of the latter had been converted into clay, and the whole rock very much softened. Such a decomposition is well known to be almost universal in the crystalline rocks of the Appalachians south of the Potomac ; and if it is only seen in rare and exceptional cases farther to the northward, this, as I have elsewhere pointed out, is due to the fact that the decomposition began and ended in the ages anterior to the drift period, and that the decayed portions which still remained were at that time removed from the surface, except in some localities which were protected from the eroding agency. I have lately had an opportunity of studying a remarkable instance of this kind in an examination made last month for the corporators of the Hoosac Tunnel.* The locality is at the western base of Hoosac Mountain, the western slope of which rises rapidly 1300 feet above the town of North Adams, in Berkshire County, Massachusetts, itself 700 feet above the sea level. Through this mountain, as is well known, a tunnel for the Troy and Boston Railroad has lately been opened, a distance of 25,081 feet from east to west. The rock of the mountain consists of mica schist and micaceous gneiss, including in its western half a great mass of harder feldspathic and quartzose strata in part a granitoid gneiss, the strata for the most part dipping to the eastward with variable angles, but with occasional western dips, apparently due to inversion. The crystalline strata of the mountain crest and sides are in many places exposed, and present rounded surfaces, often deeply grooved and striated, but with no appearance of decay. At the western base of the mountain, however, the gneissic rock is in a state of complete decomposition, which was well displayed in opening the tunnel, which, for a distance of several hundred feet, was driven through highly inclined strata so much decomposed that they were excavated with pick and shovel, and without the aid of blast- * See, for a detailed account of this examination, Dr. Hunt's report, published by the General Court of Massachusetts in House Document No. 9, 1875.

Jan 1, 1875

By L. D. Tracy

On Aug. 5 and 6,1918, and Mar. 26, 1919, the writer made an investigation of the mine-water neutralizing plant at the Calumet mine of the H. C. Frick Coke Co. The object of this plant is to develop a process of treating the water pumped from the mines so that it may be rendered suitable for use at the power plants of the mines and also at the coke ovens; at the same time, eventually producing a byproduct which will have enough commercial value to provide a sufficient revenue to place the plant on a self-sustaining basis. The Calumet mine is situated in Mt. Pleasant Township, Westmoreland County, Pa., on a branch of the southwest branch of the Pittsburgh Division of the Pennsylvania Railroad. It is about 6 mi. (9 km.) southeast of Greensburg, the county seat of Westmoreland County. The coal, which is the Pittsburg or Connellsville seam, lies at a depth of about 200 ft. (60 m.) and is brought to the surface by means of a shaft. The output of the mine averages 200,000 tons of coal annually, all of which is made into coke, either at the ovens, at the mine, or at byproduct ovens. There are 260 coke ovens at the mine. The continued development of the coal fields of Pennsylvania and the increased use of electric power in the operation of the mines has brought the problem of an increased water supply for the plants to the attention of the coal operators. This is especially true in the Connellsville coking region, where large quantities of water are used in quenching the coke at the ovens. Many of the streams receive the drainage from the mines; and as this water is highly acid and contains sulfur in various forms, some method of treatment is necessary to render it suitable for use at the plants of the mines. With this end in view, the H. C. Prick Coke Co., about 4 years ago, installed at its Calumet mine a plant for experimental purposes, in an endeavor to develop a process that would provide a maximum amount of suitable water at a minimum cost. From a purely technical point of view, the result of these experiments has been encouraging. The company is now endeavoring to place the plant on a commercial basis.

Jan 1, 1922

By Joseph Singewald

INTRODUCTION FOR a number of years Russia, India and Brazil have outranked .all other countries as producers of manganese ores. During the 5 years immediately preceding the European war, the average annual production of Russia was 844,000, of India 694,000 and of Brazil 200,000 long tons. Since the outbreak of the war there has been a considerable falling off in the Russian and Indian production, particularly in the former, whereas the production of Brazilian ores has been greatly increased, amounting in 1914 to over 250,000 tons and in 1915 to nearly 350,000, with conditions favorable for a still larger production in 1916. Manganese is one of the few industrially important metals that are not produced in the United States in quantity commensurate with our needs, so that we have been compelled to import annually about 300,000 tons, having a value of over $2,000,000, and these ores have been obtained from the three countries mentioned above. Their rank as contributors to our imports of manganese ores was India, Russia, Brazil; and in 1913, Brazil contributed only one-fifth. During the past 2 years Brazil has furnished rapidly increasing quantities to this country, and, with the falling off of imports from India and Russia, has become our principal foreign source. In 1914, Brazil furnished two-fifths of the imports and more than India or Russia, and in 1915 over nine-tenths. The manganese ores of Brazil are consequently of more than usual interest to us at this time.

Jan 10, 1916

By H. Rush Spedden

Antoine M. Gaudin was a vigorously creative man and throughout his career an internationally respected leader of his chosen profession of mineral engineering. To his professional colleagues and clients and to his former students he was both "Professor Gaudin," their wise, inspiring, and enthusiastic teacher, and "Tony," their, warm and beloved personal friend. Thus, his teachings and his unique inquisitive-creative approach to problems live on and grow in the accomplishments of his students. Antoine Gaudin was born at the turn of the century in Smyrna, Turkey, where his father was general manager of a French-owned railroad. It was there that he spent his earliest years, literally in the shadow of classic marbles from diggings at the site of Aphrodesias, which his father had rediscovered. From this, Tony developed an appreciation of the arts. He eventually surrounded himself with art treasures; he reveled in the beauties of nature, and he cherished his choice collection of rhododendron and azaleas. His artistic traits led him to take up painting when his daughter, Elinor, sought his help in blending her tints for a water color. In typical fashion he was not satisfied until he had become adept with pastels in capturing the muted tones of distant landscapes and the technical properties of light and color. Unfortunately not many paintings were produced. His paternal grandfather was Marc-Antoine Gaudin, for many years secretary of the Academie des Sciences in Paris, and a well known chemist and mineralogist whose primary interests included the synthesis of precious stones. In an autobiographical sketch written in 1939, Dr. Gaudin recalled: "As a child I saw many of the original synthetic sapphires and rubies which my father had inherited. This, coupled with my father's avocation of mining ventures and archaeology, early decided that I would become connected with the mineral industry." One can speculate that the archeological activities of his father, the mineral systhesis experiments of his grandfather, and his own early studies of mineralogy and geology formed a base from which his special talents as an experimentalist were to develop. Laboratory research under Professor Gaudin's personal guidance was often an intensive, fast-moving, and exciting experience--especially to a new graduate student. First of all, Professor Gaudin was a highly skilled observer with seem-

Jan 1, 1976

By Hugh S. Spence

IN the winter of 1941-42, muscovite mica was discovered by a young prospector, Justin Purdy, in the township of Mattawan, Nipissing District, Ontario, a few miles north of the small settlement of Eau Claire, which lies on the main Transcontinental Highway (No. 17) between Mattawa and North Bay. Muscovite had been known for many years to occur in the general Mattawa region, and various small efforts at production had previously been made by individuals working scattered deposits in the area. These minor activities, however, had never led to production of any consequence or the discovery of any important mica bodies. The Purdy finds were made in a heavily timbered, mountainous area lying about three miles north of the low-lying settled land along the highway, and in a section not hitherto prospected. The mica taken by Purdy and two partners from surface outcrops proved so remarkable in point of size of trimmed sheets that the find attracted considerable attention, and the area surrounding the three claims taken up by the prospectors was quickly blanket-staked by various interests. Though a number of other mica-bearing pegmatite dikes were 'found later on these stakings, none proved as rich as those on the original Purdy ground; very little commercial mica was obtained from them and attempts to develop them were short-lived. Purdy and his partners sold their initial production to dealers in Ottawa and Hull, where the Canadian mica industry long has centered. Young Purdy, unfortunately was killed in a motor accident in the early summer of 1942. His father continued mining operations for a few months and produced and sold a considerable amount of mica. In October 1942 the Purdy holdings were acquired by Inspiration Mining and Development Co. of Amos, Quebec, which had been active in staking in the area. This company formed a subsidiary, Purdy Mica Mines, Limited, to develop the property. Under the energetic management of Joseph R. Norrie, rapid progress was made, and production soon attained important proportions. Realizing from the outset the unusual character and potential value in the war effort of the Purdy discovery, the Metals Controller, Department of Munitions and Supply, at once arranged with the Department of Mines and Resources for an official geological report on the area, and also drew the attention of the War Production Board in Washington to what seemed likely to prove a highly important source of strategic-quality mica. Officials of WPB were sent up in the summer of 1942 to inspect the property,

Jan 1, 1947

By W. A. Backofen

THE preferred orientations, or textures, resulting from many of the various methods for testing and forming metals have been the subject of numerous investigations.1,2* Despite this large amount of work, however, only a few limited studies have been made of the texture that is developed by torsional deformation. Ono3 found that in severely twisted wires of copper and aluminum a [Ill] direction lies parallel and a [1101 direction perpendicular to the longitudinal axis of the wire. Sachs and Schiebold4 have reported that a double-fiber texture exists in a twisted aluminum wire with both the [Ill] and [loo] directions parallel to the axis of the wire. Twisted iron wires have also been examined by Ono.8 Both the [1101 and [1121 directions were reported as parallel to the axis of the wire. Goss5 concluded from a study of twisted rods of a low-carbon steel that the preferred orientation existing at fracture is quite complex, but that many grains have a [1101 direction parallel to the axis of the wire. In addition to the earlier experimental work, some suggestions have been made about the possible nature of the torsion texture. These suggestions are based on the results of many experiments which indicate that the cold-working texture of a particular metal is largely determined by the geometrical change in shape that the metal undergoes during plastic deformation.1,6 Hibbard and Yen7 have considered the problem of deformation textures and have presented an analysis which is able to explain why equivalent changes in shape should yield similar textures. Therefore, a knowledge of the principal strains associated with torsional deformation would seem helpful in the interpretation of the torsion texture. The necessary analysis has been made of the state of strain in an element of metal lying in the surface of a cylindrical rod or tube that has been subjected to pure torsion.8,9 This analysis shows that the directions of the principal normal strains rotate continuously within a torsion specimen while it is being twisted. After the first infinitesimal amount of twisting, these directions make angles of 45" with the longitudinal axis of the bar. They rotate from this position as twisting proceeds, and after an infinite amount of twisting, the direction of the principal tensile strain is perpendicular, and the direction

Jan 1, 1951

With only one certain exception coal was never used by the Indians, before white men came to America, for any purpose except as an ornament or for paint. Within the past few years it has been discovered that the Hopi Indians in Navajo County, Arizona, used lignite for burning pottery, about 1000 A. D., as dated by tree rings. They were able to obtain a clear color in their ware that could not be obtained with brushwood fires. The coal was mined by hammers from outcrop openings, some of which can still be seen, and the tools used have been found in them.1 (See also p. 376.) Small figurines made of splint or cannel coal have been found at various localities in western New York, in Ohio and possibly other places, evidently made for ornaments. There is no reason to think they are of any greater age, if as old, as that mentioned above. Some crushed coal was used by the Indians as a black pigment in painting themselves, but apparently the eastern Indians never used coal for any other purposes. Some think that several tribes of Indians in the Northwest, along the Missouri, used coal as fuel, the basis being a statement attributed to Radisson about 1660. In the Jesuit Relations of 1659-1660 it was stated that Radisson anti Groseilliers had just returned from a visit to Lake Superior and beyond. "In the country of the Poualak, which means 'warriors' they say `as wood is scanty in supply and small in size in their country, nature has taught them to make fire with coal from the earth (charbon de terre) and to cover their cabins with skins.'"2 This statement was only hearsay with the good fathers, and the reputation for veracity of the two explorers is not of the best, and it is extremely probable that instead of coal they used turf, dry grass or buffalo chips. In fact in Radisson's Voyages' he does not mention coal at all in his account of the third voyage, when he was supposed to have seen it used. His accounts of his travels are badly mixed, and he and his companions were much better travellers than narrators. None of the early travellers up the Missouri River saw any evidence even then that the Indians were familiar with the use of coal. In the writer's opinion it is unlikely that coal was used as stated by the Jesuits.

Jan 1, 1942

By Hugh S. Spence

In the winter of 1941-42, muscovite mica was discovered by a young prospector, Justin Purdy, in the township of Mat-tawan, Nipissing District, Ontario, a few miles north of the small settlement of Eau Claire, which lies on the main Transcontinental Highway (No. 17) between Mattawa and North Bay. Muscovite had been known for many years to occur in the general Mattawa region, and various small efforts at production had previously been made by individuals working scattered deposits in the area. These minor activities, however, had never led to production of any consequence or the discovery of any important mica bodies. The Purdy finds were made in a heavily timbered, mountainous area lying about three miles north of the low-lying settled land along the highway, and in a section not hitherto prospected. The mica taken by Purdy and two partners from surface outcrops proved so remarkable in point of size of trimmed sheets that the find attracted considerable attention, and the area surrounding the three claims taken up by the prospectors was quickly blanket-staked by various interests. Though a number of other mica-bearing pegmatite dikes were found later on these stakings, none proved as rich as those on the original Purdy ground; very little commercial mica was obtained from them and attempts to develop them were short-lived. Purdy and his partners sold their initial production to dealers in Ottawa and Hull, where the Canadian mica industry long has centered. Young Purdy, unfortunately was killed in a motor accident in the early summer of 1942. His father continued mining operations for a few months and produced and sold a considerable amount of mica. In October 1942 the Purdy holdings were acquired by lnspiration Mining and Development Co. of Amos, Quebec, which had been active in staking in the area. This company formed a subsidiary, Purdy Mica Mines, Limited, to develop the property. Under the energetic management of Joseph R. Norrie, rapid progress was made, and production soon attained important proportions. Realizing from the outset the unusual character and potential value in the war effort of the Purdy discovery, the Metals Controller, Department of Munitions and Supply, at once arranged with the Department of Mines and Resources for an official geological report on the area, and also drew the attention of the War Production Board in Washington to what seemed likely to prove a highly important source of strategic-quality mica. Officials of WPB were sent up in the Summer of 1942 to inspect the property, and so impressed were they with the possibility that it might become of high

Jan 1, 1948