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By J. A. Fellows, Earnshaw Cook, H. S. Avery

THE increased use of heat-resistant alloys (26 per cent Cr, 12 per cent Ni; 16 per cent Cr, 35 per cent Ni; 12 per cent Cr, 60 per cent Ni; etc.) in recent years has been accompanied by continued demands by the consumer for improvement in properties. The manufacturers of these materials, of necessity, have resorted to more critical studies of the basic causes of variations in fundamental properties. To keep pace with the need for augmented information, previous techniques of investigation have been refined and new test methods and instruments created. It is the purpose of this paper to describe the apparatus, experimental technique and precision of measurement that were employed in the exploration of properties of heat-resistant alloy presented in a companion paper.? The detailed precautions in experimental procedure essential for attainment of accurate and comparable data at elevated temperatures cannot be too highly emphasized. THE CREEP TEST Since the fundamental concepts of creep testing have been recognized for the past 20 years, present interest is restricted to refinements in equipment and experimental procedure. The creep-test laboratory constructed for the American Brake Shoe and Foundry Co. is designed to permit 1000-hr. tests in the temperature range of 1200° to 2200°F. with a choice of applied stress extending from 50 to 50,000 lb. per sq. in. in increments of 50 lb. per sq. in. To simplify the calculation of weight combinations, the loading beams (Fig. I) are provided with counterweights to eliminate the tare. The precision of the knife-edges (10.1 ratio) is such that a 10-gram weight placed on the upper specimen grip will be exactly balanced by a 1-gram weight attached to the loading shackle. Check of the loading weights proved the maximum error to be 0.06 per cent. Axial alignment is provided by crossed knife-edges in the grip seats. The furnaces are similar in design to those of Crane and Company, Battelle Memorial Institute, and the U.S. Steel Corporation. An 80 per cent Pt, 20 per cent Rh No. 19 B. and S. gauge wire is used as the heating element. The details of construction are shown in the radiograph reproduced in Fig. 2. The windings are held in place on an alundum tube with alundum cement; the distribution of turns is adjusted to give a maximum temperature gradient of ± 1°F. over a 4-in. gauge length (Fig. 3). To avoid sharp temperature differentials at the ends of the test section, the length of the furnace is four times the gauge length. Sixteen-inch coupons are used to reduce the temperature of the threaded

Jan 1, 1942

By K. R. Janowski, H. Conrad

As part of a program to establish the effect of crystal imperfections on laser output, a detailed study was made of the dislocation structure of ruby crystals obtained from varioius sources. Using KHSO4 as an etchant, a detailed mapping of the dislocation structure on the (0001) and the (1150) planes was carried out. A less extensive study was made of the rhombohedral planes. The average dislocation density on the basal plane was 1.5 to 3 x 106 cm&apos;2 and on the (1120) planes -5 x 10&apos; cm-2. Howe7!er, considerable variation existed between areas on a given plane. The subboundaries in the basal plane tended to lie along [1100] type directions while those on the (1120) plane tended to lie: a) parallel to the basal plane, b) along truces of the (1101) plane, and c) along normals to the traces of the (0001) planes. The orientations suggest that mang of the dislocations lie on the (0001), (1701), and (1150) planes A Laue back-rellection nnalysis Of c-axis wander in one crystal revealed a gradual increase in misorientation from me end of the crystal to the other, with a maximum variation of 1°35&apos;. Slight etching of a mechanically polished crystal revealed mumerous polishing scratches, suggesting the existence of a plastic flow layer. It is recognized that chromium concentration, lineage, and other crystalline imperfections play a role in the efficiency of ruby lasers.&apos; Consequently, it is desirable to establish in detail the imperfection structure of ruby crystals to be used as lasers. Some exploratory work along this line had already been done by Barnes&apos; and Dils and Martin.&apos;" How- referred to as the morphological system, as described by Kronberg.4 The Miller indices given in the present paper will be based on this morphological system. In this system, the three common growth planes are the (0001), the {1120}, and the {1101}.5 Since these planes are of high stability, it is expected that they are most suitable for study by the etch-pit technique. In the present investigation, a detailed mapping of the dislocation structure was carried out for the (0001) and the (1130) planes. A less extensive study was made of the etch-pit structure on rhombohedra1 planes. An analysis of dislocations in sapphire (the ruby host) was first made by kronberg,4 who postulated that slip on the (0001) plane occurred by motion of dislocations with Burgers vector 1/3 <1150> and that these dislocations might dissociate into quarter partials. An etch-pit technique using boiling phosphoric acid was developed by Scheuplein and Gibbs6, 7 for identifying dislocations intersecting the (0001) planes and the planes near (2021) in sapphire. Al-ford and Stephens8 were able to reveal dislocations on the (0001) and {1120} planes in sapphire and ruby by etching in fused potassium bisulfate (KHS04) at 675°C. The termini of basal dislocations [(000l), <1120>] were revealed by Palmour and Kriegel9 on {1120} and {1010} by thermally etching sapphire. Bond and Harvey10 were able to decorate dislocations in sapphire by adding 1 pet by weight of ZrO2 to the Al2O3 powder used in the growth of the crystals by the Verneuil technique and then heating the grown crystals for 4 hr at 1500°C. They found, using optical transmission microscopy, that many dislocations had straight segments which were parallel to one of the six [1120] directions in the basal plane. Single dislocation lines curved smoothly from one alignment to the other, turning through angles of 60 to 120 deg. Also observed were isolated hexagonal loops, approximately 10 µ in diameter, the sides of which lay along the same directions as did the longer dislocations. MATERIAL AND ETCHING PROCEDURE The ruby specimens used in this study (all containing approximately 0.04 pet Cr) had been obtained from four different sources: Linde Co., Meller Co., Valpey Crystal Corp., and those grown at Aerospace Corp.* For the initial phase of this study, several specimens were cut from the slab shown schematically in Fig. 1 which had previously been cut from a disk boule obtained from the Linde

Jan 1, 1964

By D. D. Pollock, D. I. Finch

PREVIOUS work&apos; on a four-component system (Cu-Mn-Ni-Fe) resulted in the development of consistent relationships between the chemical composition and the electrical properties of these manganin-type alloys. The present study was undertaken to develop alloys with temperature coefficients of resistivity and thermoelectric properties more desirable than those of the manganin type, and to determine whether the relationships which had been found for the Cu-Mn-Ni-Fe alloys could be extended to five-and six-component alloy systems. PREPARATION OF ALLOYS The five- and six-component alloys were made from OFHC copper rod, ARMCO iron, electrolytic nickel, manganese cathode chip, and special high-purity aluminum and indium. A Cu-Mg master was used for deoxidation. The compositions of these materials are given in Table I. The alloys were melted and cast as indicated previously,&apos; except that no cover was used and the melts were teemed. EXPERIMENTAL PROCEDURE The finished wire size of 0.0808 in. diam was again selected for the reason that the test specimens would be self-supporting, thus eliminating any extraneous effects which might have been introduced by winding smaller diameter wire on spools or forms. The following tests were performed on the finished wires: A) Chemical Analyses—All of the components of these alloys were determined by premium gravimetric methods. The principle residual impurity contained in these alloys is 0.008 pct Mg (by weight), maximum. Tables II and 111 present the mean analyses computed from at least four determinations of each constituent. B) Electrical Characteristics—The test procedures forthe determination of the thermal emf vs copper, resistivity, and the resistance-temperature relationship are given in detail in Ref. 1. It was also shown that the resistance-temperature relationship is of the form Pt = P,n + At -B/2, [1] where P, is the resistance at t C expressed in percent of a given standard resistance, P, is this per- 0 centage at 0°C, and A and B are constants for a given, properly treated, composition. The results of the electrical tests are also given in Tables II and 111. INTERPRETATION OF DATA The modified Linde2 formula, known to be valid for dilute binary solid solutions, was applied to the complex Cu-Mn-Ni-Fe type alloys. This relationship is of the form where Ap is the increase in resistivity. Zb the valence of the solute, Zn the valence of the solvent, and K and K are designations assigned by Robinson and Dorn3 to the constants for the periodic group to which solute element belongs. The units of K, are -cm per valence difference squared per at. pct; those of K2 are pa-cm per at. pct. For the sake of brevity, these units are not repeated in the following discussion. Calculations were made to determine if this formula was accurate for five-component systems. No experimental studies were made of the Cu-In and Cu-A1 binary systems. The effects of indium additions upon the resistivity of copper are given by Linde. These data, along with those of the effects of Mn and Fe, permitted the calculation of the effects of Al.

Jan 1, 1959

By R. E. Zimmerman

Wide attention is being placed upon various methods for cleaning the fine sizes of bituminous coals. The author describes and analyzes the results achieved on wet concentrating .tables of modern design on unclassified feeds of - 1/2 in. particle sizes, including tests on high-sulphur coals.

Jan 1, 1950

By H. I. Aaronson, H. A. Domian

ELectvon-probe analgsis has been used to in7:estigatr the partition ot alloying- elements between aus-tenite and proeutectoid ferrite (or the Jerritic component of bainite) in high-purity Fe-C-X alloys, lsuully at tzco levels of carbon content fca 0.1 and 0.4 pct in ntost steels) at temperatures between the M, and the Ae3 in Si, mn, Ni, mo, Co, Al, Cr, Cu, and PI steels. No partition ous found during the early stages of transformation at any temperature studied in the Si, ,mo. Co, Al, Cr, and Cu steels. Partition did take place, Jrowel&apos;er, in Ihe Mn, ATi, and Pt steels, occurring in lewtperature. regions below the Ae3 of ca 130°, 65", UNDERSTANDING the mechanisms through which alloying elements influence the kinetics of austenite decomposition reactions which proceed by nucleation and 35c respectively. A break was discovered in the TTT curve for the initiation oj the proeutectoid ferrite reaction in the latter steels at the temperature at which partition began. The alloy content in ferrite at the a:y bondavy remained at constart lecels, shown experimentally to be significantly above those corresponding to eqiilib+iu??l, e&apos;en at the longest reaction times investigated (ca 1o6sec). The partition and the TTT curve observations foere rationalized on the basis of the thermodynamic treatment developed in an accompany ing paper. and diffusional growth has been a major research objective of physical metallurgy since the latter part of the 19th century. The measurements made on the dif-fusivities of carbon and of substitutional alloying elements in austenite during the 1930&apos;s and 1940&apos;s seemed to provide a useful clue as to the nature of these mechanisms. These measurements showed that the diffu-sivity of carbon is several orders of magnitude higher than that of the alloying elements at a given tempera-

Jan 1, 1967

By H. B. Pulsifer

THIS paper outlines a method for rapid production of flat, granular surfaces on many of the medium hard- alloys. Grinding wheels and fabrics on wheels are not used; the purpose is accomplished by rubbing on emery papers and on fine abrasives heaped on hand boards. The advantages of chromic acid in the solutions for etching nickel and copper alloys are explained. Steels may require an additional step in the mechanical smoothing owing to the lack of an ideal etchant. Chloric acid is a. rapid etchant for steel. Thirty-six photomicrographs illustrate the steps in smoothing and the clearness with which structures can be rapidly exposed. New structures in low-carbon steels are announced. After a little practice, many materials can be finished within two or three minutes. CUPRONICKELS In the previous papers on the metallography of copper and magnesium which the author has presented to this Institute there has been an attempt to demonstrate the advantages of minimizing the mechanical work of surfacing and depending more on chemical means; the present paper continues the research into a still wider field. It is obvious that the success of a chemical method for smoothing and etching depends almost entirely on the use of a suitable reagent. The etchant must remove the surface granulations and outline the structures. A very special type of reaction between reagent and metal must be displayed. Promiscuous corrosion or the intensification of the attack about local couples -formed by impurities or components must not be in evidence. There are several reagents that etch highly polished nickel and copper alloys very well. Acidified ferric chloride solutions, concentrated and dilute nitric acid solutions, and nitric and acetic acids in acetone have -been used to good advantage for the purpose. However, if they are expected to etch rather deeply-that is, smooth as well as characterize-the results may be far from satisfactory.

Jan 1, 1928

Jan 2, 1976

By R. C. Edwards, T. G. Kirkland, Will Mitchell

A scrubber of new design has been invented for the beneficiation of glass and chemical sands. The machine is described and its capacity and metallurgical efficiency compared with the performance of other sand cleaning devices. THREE years ago, when the Process Research Laboratory at Allis-Chalmers Manufacturing Co. sought a remedy for the increasing cost of disposing of great quantities of spent sands from foundries, R. C. Edwards developed a continuous inclined paddle scrubber which removed a substantial amount of the charred coatings from the grains with a surprisingly small amount of degradation of the sand itself.&apos; The satisfactory results obtained on foundry sand, using this piece of equipment in conjunction with classification, suggested that a similar procedure could probably be applied to the cleaning of other sands, such as those required by the glass and chemical industries. This paper describes the flowsheet and the results of tests performed on impure natural sands. The four materials tested were silica sands obtained from widely separated geographical areas. Three of the sands tested contained various amounts of iron oxide and the fourth an excessive amount of calcareous bonding material. The iron oxide was present predominantly in the form of grain coatings, which were scuffed by the paddle scrubber, and in all cases a product was manufactured which would meet one of the sets of specifications imposed by the glass industry.&apos; The Edwards paddle scrubber used in these tests consists of a rubber-lined steel cylinder 18 in. in diam and 48 in. long, mounted on a frame so that its slope can be varied 5" to 35" from horizontal. This variable slope permits controlled flow of material through the machine. Rubber paddles rotate inside the cylinder and are secured to a center shaft 2 in. square, which extends through the entire length and is turned at both ends so that it can be supported by sleeve bearings centrally fixed in the end plates of the shell. At the upper or feed end it extends through the bearing on the end plate into a sheave, to which the motor drive is connected by means of Texrope transmission. The four sets of paddles mounted on the shaft, two in each set, are made of rubber belting, 1/4 in. thick, 9 in. wide, and 16 in. long. The two paddles in each set are secured on opposite sides of the square shaft, but in the same longitudinal position along the shaft axis. In other words, the two paddles in the set operate 180" apart. Each successive set is mounted 90" from the preceding one. One end of each paddle is bolted to the square shaft and the other weighted by a steel bar, lx1 1hx9 in. long, which is attached about Yz in. from the outer tip of the paddle. By centrifugal force at proper shaft speed, these weights force the paddle surface to rub smoothly against the rubber lining of the cylinder. During operation, the sand forces its way between the paddle face and the surface of the cylinder, providing the necessary abrading action as the pulp flows by gravity down the length of the cylinder. The capacity of the machine is limited by the amount and the hardness of the coating material and by the quality of product desired. The degree of scrubbing is governed by the retention time in the scrubber, which in turn may be changed by varying the feed rate, water content of the feed, and

Jan 1, 1953

By R. C. Edwards, Will Mitchell, T. G. Kirkland

A scrubber of new design has been invented for the beneficiation of glass and chemical sands. The machine is described and its capacity and metallurgical efficiency compared with the performance of other sand cleaning devices. THREE years ago, when the Process Research Laboratory at Allis-Chalmers Manufacturing Co. sought a remedy for the increasing cost of disposing of great quantities of spent sands from foundries, R. C. Edwards developed a continuous inclined paddle scrubber which removed a substantial amount of the charred coatings from the grains with a surprisingly small amount of degradation of the sand itself.&apos; The satisfactory results obtained on foundry sand, using this piece of equipment in conjunction with classification, suggested that a similar procedure could probably be applied to the cleaning of other sands, such as those required by the glass and chemical industries. This paper describes the flowsheet and the results of tests performed on impure natural sands. The four materials tested were silica sands obtained from widely separated geographical areas. Three of the sands tested contained various amounts of iron oxide and the fourth an excessive amount of calcareous bonding material. The iron oxide was present predominantly in the form of grain coatings, which were scuffed by the paddle scrubber, and in all cases a product was manufactured which would meet one of the sets of specifications imposed by the glass industry.&apos; The Edwards paddle scrubber used in these tests consists of a rubber-lined steel cylinder 18 in. in diam and 48 in. long, mounted on a frame so that its slope can be varied 5" to 35" from horizontal. This variable slope permits controlled flow of material through the machine. Rubber paddles rotate inside the cylinder and are secured to a center shaft 2 in. square, which extends through the entire length and is turned at both ends so that it can be supported by sleeve bearings centrally fixed in the end plates of the shell. At the upper or feed end it extends through the bearing on the end plate into a sheave, to which the motor drive is connected by means of Texrope transmission. The four sets of paddles mounted on the shaft, two in each set, are made of rubber belting, 1/4 in. thick, 9 in. wide, and 16 in. long. The two paddles in each set are secured on opposite sides of the square shaft, but in the same longitudinal position along the shaft axis. In other words, the two paddles in the set operate 180" apart. Each successive set is mounted 90" from the preceding one. One end of each paddle is bolted to the square shaft and the other weighted by a steel bar, lx1 1hx9 in. long, which is attached about Yz in. from the outer tip of the paddle. By centrifugal force at proper shaft speed, these weights force the paddle surface to rub smoothly against the rubber lining of the cylinder. During operation, the sand forces its way between the paddle face and the surface of the cylinder, providing the necessary abrading action as the pulp flows by gravity down the length of the cylinder. The capacity of the machine is limited by the amount and the hardness of the coating material and by the quality of product desired. The degree of scrubbing is governed by the retention time in the scrubber, which in turn may be changed by varying the feed rate, water content of the feed, and

Jan 1, 1953

By R. C. Edwards, T. G. Kirkland, Will Mitchell

A scrubber of new design has been invented for the beneficiation of glass and chemical sands. The machine is described and its capacity and metallurgical efficiency compared with the performance of other sand cleaning devices. THREE years ago, when the Process Research Laboratory at Allis-Chalmers Manufacturing Co. sought a remedy for the increasing cost of disposing of great quantities of spent sands from foundries, R. C. Edwards developed a continuous inclined paddle scrubber which removed a substantial amount of the charred coatings from the grains with a surprisingly small amount of degradation of the sand itself.&apos; The satisfactory results obtained on foundry sand, using this piece of equipment in conjunction with classification, suggested that a similar procedure could probably be applied to the cleaning of other sands, such as those required by the glass and chemical industries. This paper describes the flowsheet and the results of tests performed on impure natural sands. The four materials tested were silica sands obtained from widely separated geographical areas. Three of the sands tested contained various amounts of iron oxide and the fourth an excessive amount of calcareous bonding material. The iron oxide was present predominantly in the form of grain coatings, which were scuffed by the paddle scrubber, and in all cases a product was manufactured which would meet one of the sets of specifications imposed by the glass industry.&apos; The Edwards paddle scrubber used in these tests consists of a rubber-lined steel cylinder 18 in. in diam and 48 in. long, mounted on a frame so that its slope can be varied 5" to 35" from horizontal. This variable slope permits controlled flow of material through the machine. Rubber paddles rotate inside the cylinder and are secured to a center shaft 2 in. square, which extends through the entire length and is turned at both ends so that it can be supported by sleeve bearings centrally fixed in the end plates of the shell. At the upper or feed end it extends through the bearing on the end plate into a sheave, to which the motor drive is connected by means of Texrope transmission. The four sets of paddles mounted on the shaft, two in each set, are made of rubber belting, 1/4 in. thick, 9 in. wide, and 16 in. long. The two paddles in each set are secured on opposite sides of the square shaft, but in the same longitudinal position along the shaft axis. In other words, the two paddles in the set operate 180" apart. Each successive set is mounted 90" from the preceding one. One end of each paddle is bolted to the square shaft and the other weighted by a steel bar, lx1 1hx9 in. long, which is attached about Yz in. from the outer tip of the paddle. By centrifugal force at proper shaft speed, these weights force the paddle surface to rub smoothly against the rubber lining of the cylinder. During operation, the sand forces its way between the paddle face and the surface of the cylinder, providing the necessary abrading action as the pulp flows by gravity down the length of the cylinder. The capacity of the machine is limited by the amount and the hardness of the coating material and by the quality of product desired. The degree of scrubbing is governed by the retention time in the scrubber, which in turn may be changed by varying the feed rate, water content of the feed, and

Jan 1, 1953

By R. C. Edwards, Will Mitchell, T. G. Kirkland

A scrubber of new design has been invented for the beneficiation of glass and chemical sands. The machine is described and its capacity and metallurgical efficiency compared with the performance of other sand cleaning devices. THREE years ago, when the Process Research Laboratory at Allis-Chalmers Manufacturing Co. sought a remedy for the increasing cost of disposing of great quantities of spent sands from foundries, R. C. Edwards developed a continuous inclined paddle scrubber which removed a substantial amount of the charred coatings from the grains with a surprisingly small amount of degradation of the sand itself.&apos; The satisfactory results obtained on foundry sand, using this piece of equipment in conjunction with classification, suggested that a similar procedure could probably be applied to the cleaning of other sands, such as those required by the glass and chemical industries. This paper describes the flowsheet and the results of tests performed on impure natural sands. The four materials tested were silica sands obtained from widely separated geographical areas. Three of the sands tested contained various amounts of iron oxide and the fourth an excessive amount of calcareous bonding material. The iron oxide was present predominantly in the form of grain coatings, which were scuffed by the paddle scrubber, and in all cases a product was manufactured which would meet one of the sets of specifications imposed by the glass industry.&apos; The Edwards paddle scrubber used in these tests consists of a rubber-lined steel cylinder 18 in. in diam and 48 in. long, mounted on a frame so that its slope can be varied 5" to 35" from horizontal. This variable slope permits controlled flow of material through the machine. Rubber paddles rotate inside the cylinder and are secured to a center shaft 2 in. square, which extends through the entire length and is turned at both ends so that it can be supported by sleeve bearings centrally fixed in the end plates of the shell. At the upper or feed end it extends through the bearing on the end plate into a sheave, to which the motor drive is connected by means of Texrope transmission. The four sets of paddles mounted on the shaft, two in each set, are made of rubber belting, 1/4 in. thick, 9 in. wide, and 16 in. long. The two paddles in each set are secured on opposite sides of the square shaft, but in the same longitudinal position along the shaft axis. In other words, the two paddles in the set operate 180" apart. Each successive set is mounted 90" from the preceding one. One end of each paddle is bolted to the square shaft and the other weighted by a steel bar, lx1 1hx9 in. long, which is attached about Yz in. from the outer tip of the paddle. By centrifugal force at proper shaft speed, these weights force the paddle surface to rub smoothly against the rubber lining of the cylinder. During operation, the sand forces its way between the paddle face and the surface of the cylinder, providing the necessary abrading action as the pulp flows by gravity down the length of the cylinder. The capacity of the machine is limited by the amount and the hardness of the coating material and by the quality of product desired. The degree of scrubbing is governed by the retention time in the scrubber, which in turn may be changed by varying the feed rate, water content of the feed, and

Jan 1, 1953

By AIME AIME

APROXIMATELY one third of the world&apos;s iron ore is mined in the United States; and about 80 per cent of this third is mined in the Lake Superior ore region, and about 60 per cent in Minnesota. The Lake Superior iron ore region covers a vast area in the vicinity of Lake Superior that contained in early geological times large areas of iron-bearing sediments, which today form metamorphosed iron-bearing rocks, such as jasper, chert, taconite, and slates. Concentration of the iron content chiefly through solution and resultant removal of silica produced the ore bodies we find today in rock folds as on the Menominee range, at dike or impervious wall intersections such as on the Gogebic range, and blanket-type enriched ore bodies ly¬ing on or within the ore formation, such as occur on the Mesabi and in steeply pitching ore lenses elsewhere. In many places, folding and subsequent erosion of the tops of the folded areas has resulted in steep dips in the ore formation and contained ore bodies. The upper eroded edges are mostly buried under glacial over-burden. The slightly dipping Mesabi formation is the principal exception as to steeply dipping ore bodies.

Jan 1, 1941

By Owen F. Jensen

CONSTRUCTION of a ground-water supply includes many operations, which do not end with completion of facilities. Evaluations must be made of the quality of water in various areas and the history of production. Following an analysis of geologic, hydrologic, and chemical data there must be an exploratory drilling program and a study of resulting information. When the well is completed a continuous survey of operating records and basic data is necessary, since designs for future wells are varied as more data becomes available for those already completed. As the following discussion must be limited to a single undertaking, the customary procedure will be outlined for development and construction of a ground-water supply in which more than three wells are involved. Parts of this procedure are applicable for all ground-water supplies. Three possible sites were selected for construction of a paper mill. The problem was that the industry daily required approximately 15 million gallons of water of the best quality available; however, if water of the best quality were not available in the desired amount, water of a poorer quality could be used up to half the required amount, about 7 million gallons. In the preliminary survey approximately 1500 to 2000 square miles were covered for each site. Collected data consisted of several hundred electric logs of oil and gas wells; reports by the U. S. Geological Survey on ground-water resources of localities in and near the area; unpublished records of several hundred water wells including chemical analyses of the water produced and drillers&apos; logs of the wells; records of periodic water-level measurements made in observation wells by the USGS; topographic maps drawn up by USGS and by army engineers; and highway and county road maps. A preliminary report based on study and evaluation of these data was presented to the client, recommending the site with the most favorable and economical ground-water conditions. The study indicated that water of the quality and quantity desired could be developed. In this particular area there were indications that the aquifer could be separated into two zones con- taining water of different chemical character. This chemical character varied somewhat with area, but principally with depth, a factor which later proved an economic advantage in design of the well field. After studying the preliminary report, the client weighed other economic factors as well as ground-water advantages and selected a plant site. Authority was given to proceed with detailed study of the chosen area. Evaluation of preliminary data concerning the area indicated that it should be supplemented with additional information derived from actual exploratory drilling and testing. A flexible plan of exploratory drilling was devised so that data obtained as each test hole was drilled could be correlated with existing data and additional test holes could be located and drilled accordingly. Specific data to be obtained from each test hole were: samples of all formations penetrated; the driller&apos;s descriptive log of formations; electric logging surveys; one or more samples of water from selected water-bearing formations; temperature; and water levels and their recovery after periods of production. The area studied in such detail was approximately 400 square miles. Choice of location for the original test holes was based on the preliminary study. The pattern for these test holes was designed to require a minimum number of holes and to allow for interpolation of data between two, three, and four holes. Geologic, hydrologic, and chemical data gathered after completion of the first four test holes showed that the north section was the most desirable in the area, which was then reduced from the original 400 square miles to about 150 square miles for more detailed and intensive study. On the basis of findings from the current test a tentative well field was laid out and a drilling program devised. One test hole was located on the actual plant site and later developed into a small pilot production well equipped with a deep well turbine pump. Water from this well was used for general construction requirements. Another test hole drilled near the pilot production well and adjacent to the proposed route of the well-collection system was used during the pumping test of the pilot production well to determine the degree of interference. From the data thus obtained, calculations were made to determine the coefficients of transmissibility and storage. Three additional holes

Jan 1, 1955

By F. Robertson Jones

IF the tendency toward extending the scope of the workmen&apos;s compensation system to include life, health, accident, old age, and unemployment insurance for workers is not promptly altered, I believe there will be a complete breakdown of that system. This is not because of any objections, there may he to requiring industries to provide these additional forms of protection in whole or in part to their employees. It is rather because our workmen&apos;s compensation laws, their scale of benefits, and the administrative procedure under them are not adapted or suited to such situations. If the compensation principle is limited to its own proper sphere and is not enlarged so as to include all the ills that the flesh is heir to, it is practical, "workable, and beneficent. If it invades foreign realms, it is bound to grow into a veritable Frankenstein&apos; which will harm principally those it &apos;is supposed to aid, and, at the same time, will promote waste, fraud, and Industrial demoralization. Compensation risks will become almost uninsurable; the cost to business will be intolerable; and the development of sound relief measures which will give to labor the protection now sought by the uneconomic device of enlarging the compensation law territory will be retarded.

Jan 1, 1934

[RALPH ADAIR Ore Dressing Consultant Bull Mtn. Rd., Asheville, N. C. Phone 4-1693 JAMES A. BARR Consulting Engineer Mt. Pleasant, Tennessee Washington, D.C. BEHRE DOLBEAR & COMPANY Consulting Mining Engineers and Geologists It Broadway New York 4, N. Y. I. R. BERENT Engineering Consultants and Contractors Mineral Exploration, Mine Evaluation, Mine Designs and Mine Management 156, Ataturk Bulvari-Ankara, Turkey BLANDFORD C. BURGESS Registered Professional Engineer Mining Consultant Monticello, Georgia GLENVILLE A. COLLINS Mining Engineer Uranium examinations Cable "Coins" 8 Howard-Canfleld Bldg. Santa Barbara, Calif. COWIN & CO. Mining Engineers and Contractors Consulting Shaft & Slope Sinking Appraisal Mine Development Reports Mine Plant Construction I-lath St. S. W. B&apos;ham, Ala., Phone 56-5566 MILTON H. FIES Consulting Engineer Rooms 1201-2. Albama Power Co. Bldg. Birmingham, Alabama]

Jan 1, 1952

Jan 1, 1915

By A. L. Mular

lnput energy-size modulus relation at small reduc-tion ratios is expressed by Et = (M, -Mt) k;. In some cases 13 is close to Schuhmann&apos;s distribution modulus a in value. Experimental results in conjunc-tion with the equation demonstrate the fact that energy input which produced fracture is not expended on unbroken starting material inside the mill at any time. Recently, schuhmann1 derived the Charles equation2 using the postulate that complex com-minution operations can be considered as a summa- tion of many comminution events. The fragments resulting from each event are assumed to follow the Gaudin-Schuhmamn distribution. In his derivation, Schuhmann implies that the size distribution of the total mass of a material is determined by the fraction of that mass actually subjected to comminution. Consider a feed to contain a volume, Vo, of uni- formly sized homogeneous material. After t seconds of grinding, let the volume of broken material be Vo - Vt where Vt is the volume of starting material not yet broken. The size distribution of the broken material is given by: where V is the cumulative volume less than size X, and k, is the size modulus of the broken material at time t. The distribution for the total volume at this

Jan 1, 1962

(Members are urged to send in for this column any notes of interest concerning themselves or their fellow-members.) Members and guests who called at Institute headquarters during the period July 10, 1916 to August 1, 1916: W. A. Barnes, San Francisco, Cal. W. J. Mead, Madison, Wis. W. L. Bell, Davenport, Fla. Charles Mentzel, San Pedro, N. M. James P. Clarke, Jr., Little Rock, Ark. H. H. Miller, New York, N. Y. R. A. Carhart, Mitchell, S. D. W. E. Pomeroy, El Paso, Tex. G. M. Colvocoresses, Humboldt, Ariz. M. K. Rodgers, Los Angeles, Cal W. E. Defty, Phoenix, Ariz. S. C. Rodgers, Guanajuato, Mex. Carl F. Dietz, Worcester, Mass. John M. Baker and Hamilton W. Baker have resigned as general manager and mine superintendent respectively of the Baker Mines Co., of Oregon. After Aug. 1, their address will be 43 Emerson St., Denver, Colo.

Jan 9, 1916

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