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By T. Sterry Hunt

BUT little was known of the coals of Southeastern Ohio until the present survey of the State under Dr. Newberry began its work. The results of the geological investigations of Prof. E. B. Andrews in this region, and of the chemical investigations of Prof. T. G. Wormley, both of which appear in the reports of the survey for 1869 and 1874, and more recent special reports by the former, together with some data for which I am indebted to the kindness of Dr. Newberry, and my own limited observations, have served me for the preparation of the following notice of the coals lying on the western border of the great Appalachian coal-basin in the region drained by the Hocking River and its tributaries, and belonging to the Lower Coal-Measures. Some uncertainty exists as to the place in the succession of the lower coals to be assigned to the seams known and mined in the Hocking Valley. It is the opinion of Prof. Andrews that the inequalities of the original surface were such that we cannot identify in that region the lowest coals known in Northwestern Pennsylvania and the contiguous parts of Ohio, but that we must rather count from above downwards. These conclusions Dr. Newberry is not prepared to accept, and further researches will be necessary before certainty can be attained in this matter. Meanwhile it seems, from a study of its relations to the Pomeroy or Pittsburgh seam, that what is known as the great vein of the Hocking Valley, occupies the horizon of the Upper Freeport coal, E of the Pennsylvania survey, or No. 6 in Dr. Newberry's enumeration, counting from the base. This seam, in the region in question. assumes certain characteristics which, taken in connection with its geographical position, give it a great importance among the coals of the State. The area to be noticed includes the whole or parts of several townships in Perry, Hocking, Vinton, and Athens Counties, lying near the margin of the basin over which the vein in question assumes the character of a dry-burning or splint coal, and has a thickness varying from six to ten and even twelve feet. Its precise limit southward cannot at present be clearly defined, but it has been found as far south as the line of the Marietta and Cincinnati Railroad, with a thickness of six feet, and is mined at various points along the valley of the Hocking River, near Nelsonville, where it attains six or seven feet. To the northward, along the tributaries of this river, Sunday and Monday

Jan 1, 1874

By M. I. Jacobson, M. L. Hammond

The solid solubilities of high-purity silver, aluminum, chromium, copper, and iron in zone-refined beryllium have been determined. Diffusion couple sandwiches of beryllium with aluminum, copper, and silver foil and diffusion couples of beryllium with two-phase alloys in the Be-Cr. Be-Fe, and Be-Ag systems were analyzed by electron beam micro-probe techniques. This paper describes the material used, the experimental methods for preparing the diffusion couples and the alloys, the analytical techniques, and the results obtained. The results are compared with those of previous investigators who used materials of lower purity. ~NVESTIGATORS of beryllium phase diagrams have often been hampered in their interpretations of certain phase boundaries because of the relatively low purity of the beryllium used. This has sometimes resulted in the appearance of three phases in the regions where only two should exist. Advances in purification methods, specifically zone refining, have made available beryllium that is considerably purer than the material previously used for phase diagram studies. The primary object of this investigation was to reex-amine portions of the beryllium-rich end of the binary systems of beryllium with silver, aluminum, chromium, copper, and iron to determine more accurately the limits of terminal solid solubility. The five elements—silver, aluminum, chromium, copper, and iron—include some which are commonly found as the major impurities in beryllium, some of which are being used as solid-solution alloying elements, and some of which are used in ductile matrix alloys. They are thus of considerable importance to physical metallurgists who must work with beryllium but who must rely on the present inaccurate or incomplete diagrams. The determination of more reliable diagrams would aid researchers concerned with the problems of alloying, heat treatment, and ductility. MATERIAL The beryllium was acquired from the Franklin Institute in the form of a single-crystal, 6 in. long by 1 in. in diam, zone-refined in three passes from Pechiney SR-grade beryllium bar. The principal impurities, as determined by mass spectrography at Battelle Memorial Institute, are shown in Table I. Vacuum-melted copper, silver, and aluminum, and electron-beam zone-refined iron were obtained from the Materials Research Corp. in the form of 1/2-in.- diam bars. Iodide chromium was obtained as flakes from the Chromalloy Corp. Analyses supplied with these metals are shown in Table 11. EXPERIMENTAL PROCEDURE Preparation of Diffusion Couples. Two types of dif-fusion couples were used in this study. For the copper, silver, and aluminum systems, the couples were sand-

Jan 1, 1969

By E. DeGoyler

The Furbero oil field lies in the Gulf coastal plain of Mexico between the important ports of Tampico and Vera Cruz and about one-third of the distance between the two points from the latter (Lat. 20" 22' N., 97" 30' W. Gren.). It is in the State of Vera Cruz, about 14 miles west by south of the village of Papantla in the canton of the same name, and is the most southern of the developed oil fields of the Tampico-Tuxpam region being a distance of 50 miles south by east from the Potrero del Llano field and 42 miles in the same direction from the Alamo field. The field has been developed by the Oil Fields of Mexico Co. and is in the midst of a large block of lands owned or leased by them. Communication is through the port of Tuxpam with which it is connected by a narrow-gauge railway and 6-in. pipe line some 52 miles in length. This field is of more than ordinary interest since it represents a type of oil deposit hitherto unknown. So far as I am aware, no other commercially valuable deposit of oil is known to occur under conditions of accumulation similar to those found here. The igneous nature of the so-called 'sand' encountered in drilling was not recognized until a number of wells had been drilled; and it was not until recently that the geological relations of the sill or laccolith, which gives rise to the accumulation of oil, were known and the so-called 'anticline' was known to be, in part at least, the result of igneous intrusion. Geological surveys in this general region were made in 1900-1901 by W. H. Dalton and in 1907-1909 by P. C. A. Stewart, F. W. Moon, Leonard V. Dalton, and Dr. Max Muhlberg. More recent surveys have been made, however, under the direction of the author, by E. L. Ickes, B. C. Belt, B. Hartley, and Harve Loomis. Notes of the earlier examinations were not available with the exception of the report by Dr. Muhlberg who apparently first recognized the true nature of the Furbero intrusion. This paper is indebted to his work and that of the more recent surveys for much of the detail regarding stratigraphy and to Messrs. Percy Furber and Arthur C. Payne, President and General Manager of the Oil Fields of Mexico Go. for permission to publish, and for much of the in-

Jan 1, 1916

By E. DeGolyer

(San Franciso Meeting, September, 1915) I. INTRODUCTION THE Furbero oil field lies in the Gulf coastal plain of Mexico between the important ports of Tampico and Vera Cruz and about one-third of the distance between the two points from the latter (Lat. 20° 22' N., 97° 30' W. Gren.). It is in the State of Vera Cruz, about 14 miles west by south of the village of Papantla in the canton of the same name, and is the most southern of the developed oil fields of the Tampico-Tuxpam region being a distance of 50 miles south by east from the Potrero del Llano field and 42 miles in the sane direction from the Alamo field. The field has been developed by the Oil Fields of Mexico Co. and is in the midst of a large block of lands owned or leased by then. Communication is through the port of Tuxpam with which it is connected by a narrow-gauge railway and 6-in. pipe line some 52 miles in length. This field is of more than ordinary interest since it represents a type of oil deposit hitherto unknown. So far as I am aware, no other commercially valuable deposit of oil is known to occur under conditions of accumulation similar to those found here. The igneous nature of the so-called `sand' encountered in drilling was not recognized until a number of wells had been drilled; and it was not until recently. that the geological relations of the sill or laccolith, which gives rise to the accumulation of oil, were known and the so-called `anticline' was known to be, in part at least, the result of igneous intrusion. Geological surveys in this general region were made in 1900-1901 by W. H. Dalton and in 1907-1909 by P. C. A. Stewart, F. W. Moon, Leonard V. Dalton, and Dr. Max Muhlberg. More recent surveys have been made, however; under the direction of the author, by E. L. Ickes, B. C. Belt, B. Hartley, and Harve Loon-us. Notes of the earlier examinations were not available with the exception of the report by Dr. Muhlberg who apparently first recognized the true nature of the Furbero intrusion. This paper is indebted to his work and that. of the more recent surveys for much of the detail regarding stratigraphy and to Messrs. Percy Furber and Arthur C. Payne, President and General manager of the Oil Fields of Mexico Co. for permission to publish, and for much of the in-

Jan 9, 1915

By Henry P. Ehrlinger, James C. Bradbury

Tripoli is a naturally occurring, very finely divided form of silica found chiefly in some midwestern and southeastern states and used commercially as fillers and abrasives. Definitions Tripoli is a microcrystalline, finely particulate, more or less friable form of silica that appears to be the product of leaching of siliceous limestone or calcareous chert. The term was originally applied to a deposit near Seneca, Mo., that resembled material of that name found near Tripoli in North Africa (Hovey, 1894). The two deposits were subsequently found to have different physical characteristics -the North African tripoli, now called tripolite, is a diatomite, composed of the siliceous skeletons of microscopic marine plants called diatoms, and the Missouri tripoli contains no diatom remains; the term tripoli, however, continued to be used for the Missouri material and is now applied in a general way to most silica deposits similar to it in characteristics and geologic origin. In commercial trade tripoli is commonly understood to designate material from the Missouri-Oklahoma field; silica from southern Illinois, the other major producing area, is referred to commercially as amorphous silica. Each term, however, may be used commercially for material, regardless of place of origin, that has the characteristics or uses commonly ascribed to the material from one or the other major producing area. For example, in the commodity price listings, Engineering and Mining Journal routinely lists under Tripoli, prices "f.0.b. Elco, III." and "f.0.b. Seneca, Mo., and Rogers, Ark.," and under Silica, amorphous, prices "f .o.b. Ill.," and "f .o.b. Dierks, Ark." Amorphous silica, the commercial designation given to southern Illinois tripoli, is, like the term tripoli, a misnomer. Mineralogically, the southern Illinois deposits are composed of microcrystalline quartz, and no amorphous material has been detected during X-ray and scanning electron microscope investigations (Leamnson, Thomas, and Ehrlinger, 1969; Thomas et al., 1970). Soft silica is another term that has been applied to Illinois and Tennessee tripoli, presumably to distinguish it from the more compact Missouri material. It has also been used in the ceramic trade to distinguish tripoli from "hard" silica, or silica flour, produced by pulverizing silica sand (Heinz, 1937). Rottenstone, produced commercially in Pennsylvania, is similar to tripoli in that a major constituent is finely particulate silica, and its uses are much the same as those of tripoli- as abrasives and fillers. The origin of rottenstone also is similar to that of tripoli-decomposition of a siliceous sedimentary rock. The parent rock is defined as a siliceous limestone (Gary, McAfee, and Wolf, 1972; Thrush, 1968) or as shale (personal communication). Heinz (1937) quotes a brief statement describ-

Jan 1, 1975

By R. A., D. L. Sponseller, Flinn

Using specially del'eloped titanium nitride crucibles and a pressurized syslem, it has been possible to determine the solzibilitv of liquid calcium in liquid iron and iron-base alloys. At 2925°F the solubility is 0.032 wt pet Ca in pure iron. The solubility is increased by aluminum, carbon, nickel, and silicon additions, and lowered by additions of gold. An inflection in the calcium-solubility curve occurs as carbon is added to iron. At approximately 0.87 Wt pet Ca the CaC, phase replaces liquid calcium, and the calcium concentration de- creases as more carbon is added to the iron. The maximum solubility, 0.36 wt pet Ca, was obtained in iron containing 10.5 wt pet Si. The data have important implications regarding the use of calcium in process metallurgy, as well as providing an interesting test of theories of metallic solutions. Reasonably good agreement is found with theories of Alcock and Richardson and of Wagner, and criteria are suggested which permit these theories to be applied more readily to systems of this type. AT the present time relatively little is known about the factors influencing solubility in liquid metals. Information of this type is important for such matters as the control of impurity levels in liquid metals, the use of magnesium in ductile-iron production, and the use of liquid-metal alloys as fuels and coolants in nuclear power plants. One important example of restricted solubility concerns the extent to which liquid calcium will dissolve in liquid iron. This is a matter of considerable interest in view of the strong potential of calcium for removing certain impurities in steel,. as well as the ability of calcium to desulfurize, inoculate, and produce spheroidal graphite in cast irons.' Since ferrous materials normally contain other elements in addition to iron, the interactions of third elements with the Fe-Ca system are of interest. In view of the foregoing, this investigation was conducted to determine the solubility of liquid calcium in liquid iron and the effects of various third elements upon the solubility. For reasons of theoretical and engineering importance, the elements investigated were aluminum, carbon, gold, nickel, and silicon. Numerous attempts were made in the early part of the present century to determine the solubility of calcium in both liquid iron and steel, employing a variety of open-melt and closed bomb-type systems.2-4 From the results of these tests Wever concluded that calcium is insoluble in liquid and solid iron.5 These investigations were unsatisfactory in that they failed to insure the presence of a liquid layer

Jan 1, 1964

By P. W. Ramsey, E. J. Boyle, E. A. Anderson

ONLY a few zinc-rich alloys are in commercial use today, and these depend largely upon solid solution effects for their desirable properties. Typical examples are rolled alloys containing about I per cent of copper, with or without additions of elements such as magnesium,1 and die-casting alloys containing about 4 per cent of aluminum with small amounts of magnesium and sometimes copper.2 A number of elements are capable of forming alloys with zinc, which do not enter into solid solution except in limited degree. The present paper considers one such system, zinc-titanium, in which alloys having potentially useful properties in the rolled form were found. ZINC-TITANIUM SYSTEM The zinc-rich portion of the zinc-titanium diagram, as determined by standard methods in this laboratory,3 is shown in Fig. I. The portion of the diagram of significance in the present work extends from 0 to about 0.5 per cent titanium. Gebhardt4 places the eutectic at 0.45 per cent, but the evidence in favor of the composition given in Fig. I is considerable. The solid solubility of titanium in zinc is very low indeed and possibly places these alloys in a somewhat different category from the commercial alloys previously mentioned. ALLOY PREPARATION All of the alloys used in this work were prepared with titanium metal of 98.9 per cent purity. In most cases high-purity zinc (99.99 per cent) was used but sufficient work was done later to show that zinc of about high-grade composition would yield approximately equal results. Best practice in alloy manufacture seemed to be to prepare a zinc-titanium hardener by adding about 4 per cent of titanium metal to molten zinc and holding under a boric acid cover, with frequent stirrings, at 750°C. until the titanium had dissolved. The desired titanium content could readily be obtained in the final alloy by adding the calculated amount of this hardener. The alloys proved to be quite stable in composition, unless overheated, and, with reasonable temperature control, required no cover or flux to prevent loss of titanium content by oxidation. HOT-ROLLING TESTS Three alloys containing, by analysis, 0.05, 0.12, and 0.23 per cent titanium were selected for preliminary study. Slab cross sections revealed a marked grain refinement* (Fig. 2) in the two alloys of highest titanium content. Cast unalloyed zinc has a columnar grain structure similar to that shown for the alloy of lowest titanium content but without the scatter of small equiaxed grains at the center.

Jan 1, 1944

By A. H. Underwood, M. –Ls. Trépanier

INTRODUCTION The King and Beaver mines of Asbestos Corporation Limited (ACL) were joined in 1957 to form the King-Beaver mine. In 1964, ACL purchased the Johnson's Asbestos Company. The combined underground workings are a part of the King- Beaver mine. Asbestos ore is mined at the rate of 4080 metric tons per day (mtpd) to provide 15% of the company's daily requirement in the Thetford Mines area. Figure 1 shows the location of Thetford Mines. Two shafts service the underground. No. 3 shaft, 457 m deep, is used for personnel and material transportation, downcast ventilation, and ore hoisting. No. 4 shaft, 820 m to the south, is 389 m deep. It is used for material transportation and upcast ventilation. Figure 2 shows the relative locations of the shafts and the underground workings. The ore is mined by block caving. HISTORY The orebody outcropped at surface and was first mined as an open pit. Underground mining commenced when open pit mining became impractical. Shrinkage stoping, used initially, was unsatisfactory in the highly fractured ore. Sublevel stoping improved ore recovery and safety, but did not overcome the adverse effects of the un- stable rock. Observations of the rock failures indicated that block caving would be satisfactory. This was confirmed by careful investigation and testing. A method of block caving similar to that used at the Miami Copper Company was adopted. The first block commenced production in June 1933. BLOCK CAVING General A large block of ore is undercut above pre- pared drawpoints. The ore above the undercut caves by its own weight. Caving progresses up- ward as the caved ore is drawn. A large proportion of the rock breaks up in the caving action so that it will pass through the drawpoints. Oversize blocks are broken by drilling and blasting or mudcapping. Figure 3 shows the progressive stages of block caving. In the central part of the ore zone, the vertical dimension of a block is determined by the 132 metres between production levels. When isolated ore pockets are developed, the vertical dimensions of a block depend on the extension of the ore zone above the undercut. The minimum horizontal dimension of an under- cut determines the cavability of the overlying block. When necessary, caving is assisted by drilling long horizontal holes into the block above the undercut and blasting them. This procedure speeds up or restarts caving. It will not ensure complete caving of blocks having undercuts less than 30 m wide. Orebodies suitable for block caving are highly fractured and wide enough to cave freely without excessive dilution. Undercutting must

Jan 1, 1981

By F. Kurata, A. F. Bertuzzi, P. C. Davis, T. L. Gore

The phase and volumetric properties of 10 very volatile mixtures are presented for temperatures from — 200°F to above the critical points. These mixtures consisted of natural gases and of mixtures of natural gases with methane and nitrogen. Existing correlations of compressibility factors have been extended to apply to these mixtures. Existing correlations of critical pressures and temperatures do not apply to these mixtures. Methods have been developed for estimating critical temperatures of these mixtures to ± 4°F and critical pressures to 2 5 per cent. These methods apply to other volatile and very volatile mixtures. The results of this work are particularly applicable to the separation of nitrogen from hydrocarbons by low-temperature distillation. INTRODUCTION Knowledge of the low-temperature phase and volumetric properties of natural gases and of other mixtures of the light hydrocarbons is becoming increasingly important as interest in low-temperature separation processes increases. Low-temperature distillation has been used to separate ethane and ethylene from natural gas and from refinery gases for petrochemical uses. Removal of nitrogen from natural gas by low-temperature distillation has been proposed 7,20 as a means of increasing the capacity of existing gas transmission lines and of improving the marketability of the gas. Further application of low-temperature separation processes has been retarded by lack of data on the phase and volumetric behavior of mixtures at low-temperatures and at high pressures. This paper presents the results of determination of the phase and volumetric properties of 10 very volatile mixtures at temperatures from - 200 °F to above the critical point. These mixtures consisted of natural gases with methane and nitrogen. Generalized methods are presented for estimating the critical temperatures, critical pressures, and the densities of such mixtures. EXPERIMENTAL APPARATUS AND PROCEDURES The apparatus and the experimental procedures have been described in an earlier paper13. The method consists of displacing the mixture from a reservoir which is maintained at constant temperature and pressure into an agitated glass equilibrium cell which is maintained at constant temperature. The liquid level within the glass equilibrium cell was visually observed, and the pressure was measured to within & 3 psi with a calibrated Bourdon gage. COMPOSITIONS OF MIXTURES STUDIED The compositions of the mixtures studied are summarized in Table 1. The measured properties included in Table 1 will be discussed later in this paper. The sources of these gases are described below: Gas "A-1'' was obtained from the Phillips Petroleum Co. Its composition was reported in connection with earlier work." The properties of this gas were reported in an earlier paper.13 Gases "A-2, A-3, A-4" were prepared by mixing nitrogen with gas "A-1." Gas "AB-1" was prepared by mixing methane with gas "A-1." The properties of this gas were reported in an earlier paper.'" Gases "AB-2" and "AB-3" were prepared by mixing nitrogen with gas "AB-1." Gas "B" was obtained by W. W. Bodle of J, F. Pritchard & Co. from the primary separator of a well in western Kansas. Gas "C" was obtained from a Cities Service Co. pipeline at Lawrence, Kans. Gas "D" was prepared by mixing gas "AB" with gas "C."

Jan 1, 1955

By A. A. Smith, J. S. Smart, A. J. Phillips

The preparation of a sufficient quantity of high-purity copper for extensive laboratory use in the study of impurity effects has been an integral part of a research program in progress at the Central Research Laboratory of the American Smelting and Refining Co. for the past several years. Initially the degree of purity desired was that necessary to meet two essential requirements for experimental accuracy: (I) no impurity was to be present in the copper in an amount capable of producing a detectable effect on the properties to be studied, (2) even the minor changes in propertties caused by the addition of extremely small amounts of individual elements were to be measured without significant interference from contaminants. In the course of the investigation, evidence has accumulated to justify the conclusion that this copper is of exceptional purity; in fact, no impurity can be detected by any chemical method or spectrographic technique known to the authors. The present paper describes the method of production of the copper and presents some of its properties. Preparation oF High-purity Copper The elimination of impurities from commercial electrolytic copper is accomplished by a three-step purification process. The first operation consists of an electrolysis through a purified CuSO4-H2SO4 electrolyte using bagged anodes, low current density (5 amp. per sq. ft.) and low tem- perature (25°C max.). The electrolyte is prepared from commercial Cu2SO4 and is purified by heating the solution and adding I gram Fe as Fe2(SO4)3 to each 100 grams dissolved copper; sufficient hydrated oxide of copper, prepared from Cu2SO4 and NaOH, is supplied to precipitate Fe(OH)3, which carries down arsenic, antimony, tin, selenium, tellurium and other minor constituents. Silver and remaining traces of lead are removed by addition of Na2S to the acidified filtrate, which is then reatered after standing hot overnight. The cold solution is made up to 30 grams per liter Cu and 150 grams per liter H2SO4 and introduced without addition agents into the electrolytic system, which consists of a double row of hard-rubber battery boxes with the inside webbing and partitions removed, arranged in seven steps of ascending height. Electrolyte is uniformly supplied to the two highest cells by glass siphons operating from a constant-level reservoir, and flows by gravity through the bank of seven cells, entering each at the bottom and leaving at the top. Glass air lifts continuously supply the returning liquid to the constant-level reservoir for recirculation. Each cell contains three 4 3/4 by 4 3/8 by 1-in anodes cast from high-quality electrolytic wirebar copper, various lots of which have been used with equal success. The anodes are pinned to sheet copper hangars shaped to prevent crawl of the electrolyte to the multiple-wired bus bars—which would result in fouling of the contacts—-and hang inside wool flannel bags stretched over open wood frames. The deposit

Jan 1, 1941

By Howard N. Eavenson

Waste of coal, or perhaps more properly the percentage of its recovery in mining, has keenly interested me during an experience of over a half century in coal mining. In the early part of that time and until a few years after World War I the use of better mining plans and supervision resulted in an increased recovery. Since then, and particularly since controlled prices have been effective and mechanized mining has been extensively practiced, the tendency has all been toward lesser recovery in mining. The purpose of this paper is not to criticize the methods being used, which after all are the result of economic forces, nor to point to any particular mining method or to any locality where the best recovery is obtained, but to call attention to the tremendous waste of our national coal resources that is constantly continuing. A possible method of reducing this loss will be suggested, but without any illusions that it will be followed or that such attention will be paid to it. Average Recovery The actual average percentage of recovery of coal in the ground is not known. Many papers giving figures of recovery have been published but no definite base of measurement has been agreed upon by those presenting the data. As an example, the Pittsburgh bed can be considered—it has produced a greater output than any other and has been sold or leased at higher prices in place than any other coal bed. Over a large part of its area where high prices have prevailed it has been customary for many years to draw pillars. In these mines it has been usually assumed that the average recovery was higher than in other beds and percentages of recovery of 85 to 95 per cent are usually said to be realized. In all of these mines, however, it has been customary to leave from 4 to 8 in. in the bottom, and 10 to 16 in. in the roof; thus from 14 to 24 in. of coal has been left in the mines out of a total seam thickness of about 96 in., or 15 to 25 per cent of the total coal. No attempt is made to mine this coal for metallurgical purposes, owing to its impurities, although this unmined coal is of excellent quality and better than much of the coal used for steam purposes. If we add to this discard the coal usually lost in mining and those parts of the bed 'that must be left because of bad seam conditions, barrier pillars, reservations for buildings, gas and oil wells, one can easily see that the actual recovery from this bed cannot be more than 65 to 75 per cent. In addition, the rooster or rider or wild coal over the mining bed—often 3 to 4 ft. of coal, high in ash and sulphur but still good steam coal—is hardly ever mined, nor is any attempt made to mine it. It is safe to say that from a broad economic viewpoint not more than 50 to 60 per cent of the fuel value of this great seam is actually being recovered.

Jan 1, 1947

By L. Guttman

THE equilibrium diagram of the indium-thallium system was of interest to us in connection with a study of the superconducting properties of metallic solid solutions in progress at this Institute. For this purpose, a series of alloys was prepared covering the range from pure indium to 75 atomic pet TI, and X-ray diffraction patterns were obtained. Roughly speaking, the results indicated a region of continuous decrease in the axial ratio of the face-centered tetragonal structure from the value ca. 1.08 in pure indium to unity at about 23 atomic pct TI. From this concentration to the solubility limit, the structure was face-centered cubic, a form not reported by Hansen.1 At this point we became aware of the work of Valentiner,2 who had found the same structures at room temperature but had not investigated further the relationship between them. To study the transformation f.c.c.??f.c.t., and to clarify the phase diagram, we undertook the work reported in this paper and that which follows." Preparation of Alloys Pure indium and thallium* (both about 99.9 pct, as estimated from spectroscopic analyses) were weighed out in quantities sufficient to prepare 10 to 25 g of alloy of the desired concentration. (Occasionally indium was mixed with a previously pre- pared solution.) The metals were melted over a flame, in an open graphite crucible, stirred with a graphite rod, and poured into a graphite trough. The rough slug was hammered and swaged into a rod of 2 to 3 mm diam, and annealed in a drying oven at about 125°C for 1 to 2 days. Samples were taken from the rod for analysis, as well as for diffraction and other measurements. The thallium was determined by electrometric titration, using a modification of the method of Beale and co-workers.' The precision of analysis was generally about 2 0.2 pct of the thallium content. The rods were sometimes found to vary in thallium content as much as 1.5 pct from end to end, but since analyses were also made close to the segments used in the various studies, the composition was usually known as accurately as the analyses could be made. Where one less significant figure is given, the error is estimated to be ±0.4 pct of the thallium content. X-Ray Diffraction Measurements Three different cameras were used: (1) A 7 cm Debye camera, with oscillating specimen (manufactured by the Picker X-ray Corp., Cleveland, Ohio); (2) a 9 cm diam Debye camera of the type designed by Bradley;" (3) a 10 cm diam symmetrical focusing back-reflection camera (manufactured by Geo. C. Wyland, Ramsay, N. J.). Samples were prepared from the homogenized rods, either by filing under liquid nitrogen, or more often, in the form of wires or foils made by working at room temperature or liquid nitrogen temperature. Sharp patterns were obtained from specimens annealed at room temperature, although higher annealing temperatures were also used (cf. below). Generally, copper radiation was used; a few patterns were obtained with

Jan 1, 1951

By Howard N. Eavenson

Waste of coal, or perhaps more properly the percentage of its recovery in mining, has keenly interested me during an experience of over a half century in coal mining. In the early part of that time and until a few years after World War I the use of better mining plans and supervision resulted in an increased recovery. Since then, and particularly since controlled prices have been effective and mechanized mining has been extensively practiced, the tendency has all been toward lesser recovery in mining. The purpose of this paper is not to criticize the methods being used, which after all are the result of economic forces, nor to point to any particular mining method or to any locality where the best recovery is obtained, but to call attention to the tremendous waste of our national coal resources that is constantly continuing. A possible method of reducing this loss will be suggested, but without any illusions that it will be followed or that such attention will be paid to it. Average Recovery The actual average percentage of recovery of coal in the ground is not known. Many papers giving figures of recovery have been published but no definite base of measurement has been agreed upon by those presenting the data. As an example, the Pittsburgh bed can be considered—it has produced a greater output than any other and has been sold or leased at higher prices in place than any other coal bed. Over a large part of its area where high prices have prevailed it has been customary for many years to draw pillars. In these mines it has been usually assumed that the average recovery was higher than in other beds and percentages of recovery of 85 to 95 per cent are usually said to be realized. In all of these mines, however, it has been customary to leave from 4 to 8 in. in the bottom, and 10 to 16 in. in the roof; thus from 14 to 24 in. of coal has been left in the mines out of a total seam thickness of about 96 in., or 15 to 25 per cent of the total coal. No attempt is made to mine this coal for metallurgical purposes, owing to its impurities, although this unmined coal is of excellent quality and better than much of the coal used for steam purposes. If we add to this discard the coal usually lost in mining and those parts of the bed 'that must be left because of bad seam conditions, barrier pillars, reservations for buildings, gas and oil wells, one can easily see that the actual recovery from this bed cannot be more than 65 to 75 per cent. In addition, the rooster or rider or wild coal over the mining bed—often 3 to 4 ft. of coal, high in ash and sulphur but still good steam coal—is hardly ever mined, nor is any attempt made to mine it. It is safe to say that from a broad economic viewpoint not more than 50 to 60 per cent of the fuel value of this great seam is actually being recovered.

Jan 1, 1947

By Howard N. Evanenson

WASTE of coal, or perhaps more properly the percentage of its recovery in mining, has keenly interested me during an experience of over a half century in coal mining. In the early part of that time and until a few years after World War I the use of better mining plans and supervision resulted in an increased recovery. Since then, and particularly since controlled prices have been effective and mechanized mining has been extensively practiced, the tendency has all been toward lesser recovery in mining. The purpose of this paper is not to criticize the methods being used, which after all are the result of economic forces, nor to point to any particular mining method or to any locality where the best recovery is obtained, but to call attention to the tremendous waste of our national coal resources that is constantly continuing. A possible method of reducing this loss will be suggested, but without any illusions that it will be followed or that such attention will be paid to it. AVERAGE RECOVERY The actual average percentage of recovery of coal in the ground is not known. Many papers giving figures of recovery have been published but no definite base of measurement has been agreed upon by those presenting the data. As an example, the Pittsburgh bed can be considered-it has produced a greater output than any other and has been sold or leased at higher prices in place than any other coal bed. Over a large part of its area where high prices have prevailed it has been customary for many years to draw pillars. In these mines it has been usually assumed that the average recovery was higher than in other beds and percentages of recovery of 85 to 95 per cent are usually said to be realized. In all of these mines, however, it has been customary to leave from 4 to 8 in. in the bottom, and 10 to 16 in. in the roof; thus from 14 to 24 in. of coal has been left in the mines out of a total seam thickness of about 96 in., or 15 to 25 per cent of the total coal. No attempt is made to mine this coal for metallurgical purposes, owing to its impurities, although this unmined coal is of excellent quality and better than much of the coal used for steam purposes. If we add to this discard the coal usually lost in mining and those parts of the bed that must be left because of bad seam conditions, barrier pillars, reservations for buildings, gas and oil wells, one can easily see that the actual recovery from this bed cannot be more than 65 to 75 per cent. In addition, the rooster or rider or wild coal over the mining bed often 3 to 4 ft. of coal, high in ash and sulphur but still good steam coal-is hardly ever mined, nor is any attempt made to mine it. It is safe to say that from a broad economic viewpoint not more than 50 to 60 per cent of the fuel value of this great seam is actually being recovered.

Jan 1, 1946

By A. J. Phillips, A. A. Smith, J. S. Smart

The preparation of a sufficient quantity of high-purity copper for extensive laboratory use in the study of impurity effects has been an integral part of a research program in progress at the Central Research Laboratory of the American Smelting and Refining Co. for the past several years. Initially the degree of purity desired was that necessary to meet two essential requirements for experimental accuracy: (I) no impurity was to be present in the copper in an amount capable of producing a detectable effect on the properties to be studied, (2) even the minor changes in propertties caused by the addition of extremely small amounts of individual elements were to be measured without significant interference from contaminants. In the course of the investigation, evidence has accumulated to justify the conclusion that this copper is of exceptional purity; in fact, no impurity can be detected by any chemical method or spectrographic technique known to the authors. The present paper describes the method of production of the copper and presents some of its properties. Preparation oF High-purity Copper The elimination of impurities from commercial electrolytic copper is accomplished by a three-step purification process. The first operation consists of an electrolysis through a purified CuSO4-H2SO4 electrolyte using bagged anodes, low current density (5 amp. per sq. ft.) and low tem- perature (25°C max.). The electrolyte is prepared from commercial Cu2SO4 and is purified by heating the solution and adding I gram Fe as Fe2(SO4)3 to each 100 grams dissolved copper; sufficient hydrated oxide of copper, prepared from Cu2SO4 and NaOH, is supplied to precipitate Fe(OH)3, which carries down arsenic, antimony, tin, selenium, tellurium and other minor constituents. Silver and remaining traces of lead are removed by addition of Na2S to the acidified filtrate, which is then reatered after standing hot overnight. The cold solution is made up to 30 grams per liter Cu and 150 grams per liter H2SO4 and introduced without addition agents into the electrolytic system, which consists of a double row of hard-rubber battery boxes with the inside webbing and partitions removed, arranged in seven steps of ascending height. Electrolyte is uniformly supplied to the two highest cells by glass siphons operating from a constant-level reservoir, and flows by gravity through the bank of seven cells, entering each at the bottom and leaving at the top. Glass air lifts continuously supply the returning liquid to the constant-level reservoir for recirculation. Each cell contains three 4 3/4 by 4 3/8 by 1-in anodes cast from high-quality electrolytic wirebar copper, various lots of which have been used with equal success. The anodes are pinned to sheet copper hangars shaped to prevent crawl of the electrolyte to the multiple-wired bus bars—which would result in fouling of the contacts—-and hang inside wool flannel bags stretched over open wood frames. The deposit

Jan 1, 1941

By T. B. Massalski, Horace Pops

The occurrence and the temperature dependence of the athermal martensitic transformation in bcc Cu-Zn ß-phase alloys have been studied by cold-state microscopy, differential thermal analysis, and electrical -resistivity measurements. CinenzatograpJzic studies have shown that in the majority of alloys the transformation occurs in two stages. A thermoelastic phase, having a 'needlelike" uppearance, forms initially at the MS temperature and grows relatively slowly, chiefly in the edge (lengthwise) direction. With further cooling, an additional martensitic phase forms in rapid bursts at a lower temperature, MB, Both martensitic phases appear to have the same cry stallographic habit hut their modes of formation and growth are different. For the composition range studied, between 38.55 and 41.49 wt pct Zn, the habit planes determined are close to the (2.17 ,12) plane of the matrix, in general agreement with the prediction of the phenomenological theory of martensite formation. Thermal cycling through the MB temperature produces permanent plastic deformation in the 0 matrix and gradutally eliminates the typical burst phenomena. Thermal cycling only through the MS temperature produces no noticeable deformation effects. THE bcc Cu-Zn ß-phase alloys tend to become unstable at low temperatures and undergo a martensitic transformation,'-3 but the details of the transformation have not been completely determined. Following earlier metal log raphic and X-ray work1 Tichener and ever' determined by means of electrical-resistivity measurements the temperature range of the martensite transformation during continuous cooling. The transformation temperature was found to decrease with increasing zinc content, becoming about -130°C for an alloy containing 40.04 wt pct Zn. Hull and Garwood3 made a metallo-graphic study of Cu-Zn 0 brasses at temperatures down to -160°C, and determined the habit plane of the transformation product for an alloy containing 38.88 wt pct Zn. No metallographic studies below liquid-nitrogen temperatures have been reported. The martensitic transformation in ß-brass alloys can also be induced by deformation.1,4 The MD temperature corresponding to the appearance of the strain-induced martensite is some 300°C higher than that observed without strain, and hence the transformation can be strain-induced in alloys containing a higher percentage of zinc. Massalski and Barrett4 found that alloys containing as much as 51.89 wt pct Zn could be transformed into a faulted hcp structure by cold working at liquid-helium temperature. Because the details of the MS temperature and morphology reported in the literature are somewhat incomplete, a further study has been made of some of the above features. A design of a cryogenic stage for optical metallography5 has permitted the examination of specimens at temperatures down to 4.2oK, and the use of a cinecamera has permitted a study of the morphology on cooling and heating. The particular aim of the present work was to examine the transformation temperatures, the habit planes, and the growth morphology over a wide composition range in the ß-phase field. The effect of thermal cycling upon the subsequent transformation was also examined.

Jan 1, 1964

By John H. Hollomon, C. Zener

It is commonly recognized that a given material may be described as ductile or brittle only with reference to the conditions of test. Thus under the usual test conditions quartz is brittle, but under high pressures it is ductile. Salts that are brittle at room temperature become ductile at elevated temperatures. Pitch, brittle with respect to rapid loads, flows at low rates of loading. Pearlitic steel, ductile under the usual conditions of test, may be embrittled under the proper conditions of combined stresses, temperature, and rate of loading. Earlier Investigations A clear analysis of the conditions necessary for plastic flow and for fracture was first given by LudwikI1 who introduced two types of stress, the "flow stress" and the "stress at fracture." These stresses may refer to tensile or to shear stresses, or, in fact, to any type of stress. Ludwik considered these two stresses to be independent of one another, functions of the conditions of test and of the prior history of the material. For the purpose of analysis. both a Flow stress and a stress at fracture can be envisaged as functions of strain over the entire range from zero to infinite strain. Thus, the material is brittle if the stress at fracturc is less than the flow stress and ductile if the reverse is true. According to Ludwik's analysis, the problem of determining the effects of combined stresses, of temperature and of strain rate upon the behavior of metals reduces to a problem of determining the effect of these variables upon the flow stress and upon the stress at fracture. In the present paper, methods are described for determining the effects of two of these variables, temperature and strain rate, and examples are given of the dependence of tlow stress and stress at fracture, upon these two variables. The effect of combined stresses will be discussed in a succeeding paper. The flow stress may be determined from a load-diameter curve. Load-diameter curves were obtained over a wide range of temperature and over the limited range of strain rates obtainable with the lever-type Riehle machine used. The curves were then converted to an extremely wide range of strain rate by making use of the equivalence of the effects of changes in strain rate and changes in temperature, previously proposed2 and demonstrated3 by the authors. According to this principle of equivalence, strain rate e and temperature T affect the flow stress only through a single parameter-p of the form: p = eeQ/RT 111 In this equation, R is the gas constant (2 cal. per gram mol per deg. C.), and Q is a heat of activation, which varies from material to material, and may depend upon the strain, but not upon the strain rate or the temperature. There is associated with every value of p a flow-stress curve. article of strain rate and of temperature that give the same p have the same flow-stress curve. Therefore, merely by changing the temperature of test, the effect of changing the strain rate may be obtained. Thus, under isothermal conditions, the material will behave the same at

Jan 1, 1944

By C. Zener, John H. Hollomon

It is commonly recognized that a given material may be described as ductile or brittle only with reference to the conditions of test. Thus under the usual test conditions quartz is brittle, but under high pressures it is ductile. Salts that are brittle at room temperature become ductile at elevated temperatures. Pitch, brittle with respect to rapid loads, flows at low rates of loading. Pearlitic steel, ductile under the usual conditions of test, may be embrittled under the proper conditions of combined stresses, temperature, and rate of loading. Earlier Investigations A clear analysis of the conditions necessary for plastic flow and for fracture was first given by LudwikI1 who introduced two types of stress, the "flow stress" and the "stress at fracture." These stresses may refer to tensile or to shear stresses, or, in fact, to any type of stress. Ludwik considered these two stresses to be independent of one another, functions of the conditions of test and of the prior history of the material. For the purpose of analysis. both a Flow stress and a stress at fracture can be envisaged as functions of strain over the entire range from zero to infinite strain. Thus, the material is brittle if the stress at fracturc is less than the flow stress and ductile if the reverse is true. According to Ludwik's analysis, the problem of determining the effects of combined stresses, of temperature and of strain rate upon the behavior of metals reduces to a problem of determining the effect of these variables upon the flow stress and upon the stress at fracture. In the present paper, methods are described for determining the effects of two of these variables, temperature and strain rate, and examples are given of the dependence of tlow stress and stress at fracture, upon these two variables. The effect of combined stresses will be discussed in a succeeding paper. The flow stress may be determined from a load-diameter curve. Load-diameter curves were obtained over a wide range of temperature and over the limited range of strain rates obtainable with the lever-type Riehle machine used. The curves were then converted to an extremely wide range of strain rate by making use of the equivalence of the effects of changes in strain rate and changes in temperature, previously proposed2 and demonstrated3 by the authors. According to this principle of equivalence, strain rate e and temperature T affect the flow stress only through a single parameter-p of the form: p = eeQ/RT 111 In this equation, R is the gas constant (2 cal. per gram mol per deg. C.), and Q is a heat of activation, which varies from material to material, and may depend upon the strain, but not upon the strain rate or the temperature. There is associated with every value of p a flow-stress curve. article of strain rate and of temperature that give the same p have the same flow-stress curve. Therefore, merely by changing the temperature of test, the effect of changing the strain rate may be obtained. Thus, under isothermal conditions, the material will behave the same at

Jan 1, 1944

By C. Zener, J. H. Hollomon

IT Is commonly recognized that a given material may be described as ductile or brittle only with reference to the conditions of test. Thus under the usual test conditions quartz is brittle, but under high pressures it is ductile. Salts that are brittle at room temperature become ductile at elevated temperatures. Pitch, brittle with respect o rapid loads, flows at low rates of loading. Pearlitic steel, ductile under the usual conditions of test, may be embrittled under the proper conditions of combined stresses, temperature, and rate of loading. EARLIER INVESTIGATIONS A clear analysis of the conditions necessary for plastic flow and for fracture was first given by Ludwik,1 who introduced two types of stress, the "flow stress" and the "stress at fracture." These stresses may refer to tensile or to shear stresses, or, in fact, to any type of stress. Ludwik considered these two stresses to be independent of one another, functions of the conditions of test and of the prior history of the material. For the purpose of analysis, both a flow stress and a stress at fracture can be envisaged as functions of strain over the entire range from zero to infinite strain. Thus, the material is brittle if the stress at fracture is less than the flow stress and ductile if the reverse is true. According to Ludwik's analysis, the problem of determining the effects of combined stresses, of temperature and of strain rate upon the behavior of metals reduces to a problem of determining the effect of these variables upon the flow stress and upon the stress at fracture. In the present paper, methods are described for determining the effects of two of these variables, temperature and strain rate, and examples are given of the dependence or now stress and stress at fracture, upon these two variables. The effect of combined stresses will be discussed in a succeeding paper. The flow stress may be determined from a load-diameter curve. Load-diameter curves were obtained over a wide range of temperature and over the limited range of strain rates obtainable with the lever-type Riehle machine used. The. curves were then converted to an extremely wide range of strain rate by making use of the equivalence of the effects of changes in strain rate and changes in temperature, previously proposed2 and demonstrated' by the authors. According to this principle of equivalence, strain rate E and temperature T affect the flow stress only through a single parameter p of the form: p = EeQ/RT [I] In this equation, R is the gas constant (2 cal. per gram mol per deg. C.), and Q is a heat of activation, which varies from material to material, and may depend upon the strain, but not upon the strain rate or the temperature. There is associated with every value of p a flow-stress curve. Combinations of strain rate and of temperature that give the same p have the same flow-stress curve. Therefore, merely by changing the temperature of test, the effect of changing the strain rate may be obtained. Thus, under isothermal conditions, the material will behave the same at

Jan 1, 1944

Vermont State Geological Survey, Burlington, Vt. G H. Perkins, State Geologist Most of the file reports of the State Geologist of Vermont were destroyed in a flood at Montpelier two or three years ago Full sets of 17 volumes may be seen only in libraries. The Annual Report for 1928 and the Annual Report for 1930 may still be had, as well as a few copies for the following years: 1901-2, 1907-8, 1909-10, 1915-16, 1921-22, 1923-24. These are distributed without charge. Flood-damaged copies of the two vols, Geology of Vermont, by Hager and Hitchcock, cost $3 plus postage For any of these volumes address State Librarian, Montpelier, Vermont.

Jan 1, 1933