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By New kensington P. A, W. L. Fink, H. R. Freche

The investigation of aluminum alloy systems prior to 1923 was severely handicapped by the low purity of the best aluminum available. However, by that time, the electrolytic purification of aluminum had been developed by the Aluminum Company of America,(1)† and in May, 1923, there was initiated, under the direction of E. H. Dix, Jr.,(2) a program for the investigation of the aluminum-alloy systems using the purest electrolytically refined aluminum. Up to the present time 15 papers (3) have been published, most of which are on the binary aluminum systems. Work is now in progress on the ternary systems, and it seems probable that most of the future work will be on ternary systems. Therefore this survey of the binary aluminum systems investigatcd up to the present time (the sixteenth paper of the series) concludes the first phase of this program. Certain qualitative relations between corresponding portions of the various binary diagrams as well as between different parts of the same diagram were noted some time ago by R. S. Archer.(4) In the present paper these relations and others are considered quantitatively by the application of well-known thermodynamic equations or by newly discovered empirical relations. No attempt will be made here to present the history of the development of the thermodynamic equations defining equilibrium or their application to metallic systems, although a list of references is given at the end of this paper for those who are interested in this phase of the subject. Two thermodynamic equations, which will be employed extensively in this paper, are: loge x1 = - L/RT + C

Jan 1, 1934

By Miles L. Silberman, Edwin H. McKee, John H. Stewart

Three, major suites of igneous rocks were erupted in the Great Basin in middle and late Cenozoic time. The first resulted in eruption of andesitic rocks in the northern Great Basin between 42 and 34 m.y. ago. Between 34 and 17 m.y. ago this igneous activity migrated to the southwest, ending about 17 m.y. ago with the onset of crustal extension and north-south- trending Basin and Range (rift) faulting. The second volcanic suite erupted between 17 and 8 m.y. ago in the northern Great Basin. The third volcanic suite consists of andesitic and rhyolitic lavas and some basalt erupted between 22 to 7 m.y. ago in the western Great Basin along the northwest transcurrent Walker Lane fault zone. Hydrothermal ore deposits are associated with all suites of igneous rocks.

Jan 1, 1977

By Bruce W. Gonser

TIN is not yet classed as a rare metal, but it has taken a long stride in that direction in the last ten months. It is now in Group 1 of the War Production Board's critical list, along with such company as magnesium aluminum, and nickel. This is in sharp contrast with the position a year ago when the supply well exceeded demand, and tin was used when feasible in place of really scarce metals. The geographical sources of tin production in recent years are shown in Table 1. Preponderance of former production in southeastern Asia, particularly Malaya and the Netherlands Indies (but all now controlled by the Japanese). is entirely too marked to be funny. Of the 1940 known world production of 237,000 long tons nearly all was controlled by the United States, Great Britain, and their friends. Now their supply is from countries that produced only 28 per cent of that amount. This excludes China and Australia, which because of shipping difficulties and local consumption, cannot be expected to export much tin. In spite of some expected increase in production, therefore, the supply is, and will continue to stay for at least several years, way below that desired for even normal uses. Although deliveries to consumers in the United States alone

Jan 1, 1942

By Frances Hurd

WHEN 60:40 brass is heated to 825° C., given a drastic quench to obtain the beta solid solution, and reheated, various changes take place in the structure. Reheating at 200' C. causes a fine, granular, sorbitic structure to appear which has been considered alpha solid solution. These particles coalesce at higher temperatures of reheating, and at 470° C., the alpha forms twins. A further study of these transformations was considered worth investigating.

Jan 1, 1927

By R. J. Walter, W. T. Chandler

The Ch-H phase diagram was determined for by-drogen concentrations up to ChHo.9 at temperatures below 400°P'. The phase diagram includes a mis-cibility gap and a eutectoid transformation. A peri-tectoid transformation is postulated at the hydrogen-rich end of the diagram, Phase diagrams were determined for two levels oj purity, of the columbium. A single solid solution exists in the Cb-H system above 400°F. There has been considcrable disagreement among investigators concerning the system at temperatures below 400°F. Albrecht, Goode, and ~allett' proposed a miscibility gap containing two bcc phases with the two lattice parameters converging at about 140°C (285-F), and Brauer and ~erman' found a two-phase room-temperature region between 10 and 41 at. pct H. At sufficiently high hydrogen concentrations in the one-phase region, the hydrogen-rich phase was found to be face-centered orthorhombic. Wainwright, Cook, and Hopkills3 recently reported that the face centered orthorhombic hydride phase is derived from a unit cell which is slightly tetragonal with a small departure from 90 deg of the angle (y) opposite the r axis. The orthorhombic hydride phase was observed for hydrogen concentrations between 0.2 and 0.8 H/Cb atom ratio. Paxton and coworkers4 found that needlelike hydride plates formed in a hydrogen-charged columbium single crystal and suggested that this transformation possessed the characteristics of a diffusionless phase transformation. On the basis of room-temperature, X-ray diffraction data, komjathy' suggested that an order-disorder or martensitic transformation occurs. In the present study, the Cb-H system was investigated to resolve the discrepancies found in the literature for this system. PROCEDURE The columbium specimens were prepared from two heats of wrought 1/2-in.-diameter electron-beam melted columbium rod and from two columbium powders of -80 mesh size of different impurity contents. The columbium bar stock was pur chased from Urah Chmg Corp.; the 99 and 99.5 pct purity colulnbium powders were obtained from Fansteel Metallurgical Corp. and Kern Chemical Co.. respectively. The chemical analyses of the columbium bar and powders are listed in Table I. Hydrogen charging was performed by exposing the columbium specimens to hydrogen at 1 atm pressure at various temperatures. After exposure the specimens were quenched to prevent the hydrogen pickup which would take place if cooled in hydrogen, or the hydrogen loss that would occur if cooled in an inert gas. Adequate hydrogen purity was achieved by passing high-purity tank hydrogen (maximum 5 ppm total impurities) through an Engelhard catalytic Deoxo unit, magnesium per chlorate desiccant, and finally through activated charcoal at the temperature of boiling nitrogen. Activated charcoal at -321°F has been reported6 to remove impurities from hydrogen to a nondetectable level. A schematic representation of the heat-treating apparatus is shown in Fig. 1. A metal-sheathed thermocouple embedded in the colun~bium specimen was used to control the temperature during heat treatment and to pull the specimen boat into

Jan 1, 1965

By J. F. Smith, J. E. Davison

A value for the enthalpy of formation of z2 of -3.14 i 0.21 kcal per g-atom has been measured by the technique of acid solution calorimetry. This result is in quite good agreement with two earlier determinations by tin solution calorimetry and by direct reaction caloriinetry, and averaging of values determined from the three independent calorimetric techniques gives enhanced precision and accuracy with AHh8 (CaMgZ) = - 3.15 i 0.05 kcal per g-atom. For comparison with experimental data, values for the enthalpies of formation of CaMgz, SrMgz, and BaMgz of -9.8, -7.9, and -2.8 kcal per g-atom were estimated from a calculation based on the LVigizer-Seitz approximation as modified by Raimes for polyvalent elements. While complete quantitative accord between these calculated talues and available experimental data is lacking, nonetheless numerical accord is better than might be expected and, more importantly, parallel numerical trends are observed between experimental and calculated vnlues. WITHIN the past decade the enthalpy of formation of CaMg, has been determined a) from measurement of magnesium vapor pressures over binary Ca-Mg alloys,' b) by solution calorimetry with liquid tin as the solvent,' c) from measurement of hydrogen vapor pressures over ternary alloys of calcium, magnesium, and hydrogen,3 and d) by direct reaction alorimetr. The value from tin solution calorimetry is the most precise and is probably the most reliable, and this value is within the quoted uncertainties of the other three experimental results. The overall agreement among the four independent investigations is quite good, particularly so when the diversity of techniques is noted. On the basis of this agreement, CaMgz was chosen as a test material to evaluate the operation of a newly constructed apparatus for the determination of enthalpies of formation of intermetallic phases by acid solution calorimetry. This was believed to be a severe test because of the high chemical reactivity of both calcium and magnesium which reactivity presumably accounts for the fact that an early determination5 of the enthalpies of formation of Ca-Mg alloys by acid solution calorimetry yielded values significantly more negative than the four recent determinations. EXPERIMENTAL APPARATUS AND MATERIALS Experimental Apparatus. The enthalpy of formation of CaMg, was determined by measuring the difference between the heat evolved when dissolving the metallic compound and the heat evolved when dissolving equivalent amounts of unreacted metallic elements in hydro- chloric acid. This was done differentially with an apparatus consisting of twin calorimeters which were constructed to be as nearly identical as possible. The advantage of differential calorimetry is that systematic errors arising from the individual calorimeter design tend to cancel. A schematic representation of the apparatus is shown in Fig. 1. A dead air space around both calorimeters was provided by a large, thermally insulated jacket. Each calorimeter consisted of a 2-liter Dewar flask which was completely enclosed in a copper container. Each Dewar contained 1600 g of 2.5hr HCl to act as the solvent, and thermal effects resulting from solvent evaporation were minimized by covering the acid with 50 g of mineral oil. There was no detectable reaction between the acid and the mineral oil. Equivalent amounts of mechanical energy were added to the calorimeters through twin stirring rods which were driven at the same rpm by a single motor with the intent of the stirring being to maintain thermal equilibrium throughout the solvent. To calibrate the heat capacities of the calorimeters, known amounts of electrical energy could be added by passing measured voltages and currents for known times through submerged heaters, approximately 20 ohms, which were wound noninductively from Manganin wire. A 6-v storage battery was used as a power source, and a dummy heater was used as an exercise circuit to allow the battery to stabilize at a constant electromotive force before energizing one or the other of the calorimetric heaters. A type K-2 potentiometer was used to measure the potential drop across an energized heater while the current was determined from the potential drop across an external standard resistor. Times of energization were measured with an electric timer, and the electrical energy supplied to a heater

Jan 1, 1969

By W. C. Hardy, B. W. McArthur

The purpose of this work is to show application of laboratory data in calculating solution gas-drive performance of the Cisco K-I reservoir. Included herein is a diagram showing the graphical relationship between six variables common to all solution gas-drive mechanisms. With an iterative process one may assume existence of any of these six variables at a particular pressure and calculate the production performance likely to occur in a reservoir produced by solution gas drive. Four unique pressure values are described at which the material balance equation alone is sufficient to predict the cumulative volumes of gas produced. Information derived from these pressure points establishes a criterion for determining compatibility of the pressure-volume-temperature (PVT) analysis of the produced crude with the gas production history. Two averaging procedures are used to arrive at a relative permeability-saturation relationship which describes the field-wide performance. INTRODUCTION The Cisco K-1 reservoir is a lenticular-type sand structure lying at approximately 6,300-ft subsurface. It is located in the H. and T. C. Railroad Co. Block 97, SW 1/4 S 392 and NW 1/4 S 385, Scurry County, Tex. Correlation of data from logs indicated that the Cisco K-1 reservoir occupied approximately 3,218 acre-ft of space with a closure of from 15 to 20 ft. Analysis of the production data indicates that the initial formation pressure and temperature were 2,450 psig and 121°F, respectively. The bubble point occurred at 1,715 psig after production of 12,256 STB oil and 11,520 Mcf gas. Only traces of water have been produced since initiation of production. Successive material balance calculations from June, 1952, to June, 1957, showed that no initial gas cap or water influx has contributed to production of oil and that the Cisco K-1 reservoir originally contained approximately 1.44 X 10" STB of oil. THEORY Methods for calculating solution gas-drive perform-

By R. E. Frounfelker, W. M. Hirthe

INVESTIGATORS in the areas of plasticity, crystal growth, and stress analysis have a need for crys-tallographic data such as the interplanar angles. This information is utilized in the form of a stereo-graphic projection from which orientation determinations can be made. Calculations of mechanical properties, such as the critical resolved shear stress, require values for the angles between directions as well as the interplanar angles. Only a limited amount of this data is available for tetragonal crystals. The equations for these angles are relatively simple but because of the large numbers of angles involved and the infinite number of structures that could be investigated, it was decided to program these calculations on a high speed digital computer. The angle, 8, between two crystal planes (h1 k1 l1)

Jan 1, 1962

By John T. Galey

In all, 210 wellst were completed in southwestern Pennsylvania during 1939, which is 59 more than were drilled during the preceding year. Of this number, 137 were gas wells, which is a considerable increase from the 81 completed during 1938. Only 25 oil wells were completed, as against 28 in the previous year, and 28 dry holes, 6 more than last year. Shallow Development—Gas The increase in the number of gas wells is largely the result of a search for additional gas in Armstrong and Indiana Counties. Although a considerable number of wells were drilled in the latter county, the majority of them produced less than 100 M cu. ft. initial open flow. In Armstrong County, a new pool was opened in Cowanshannock township, producing from the third Bradford sand. Several large wells were obtained there, one of which produced an initial of nearly 12 million cu. ft., with a reservoir pressure of 1100 Ib. However, the productive area has been fairly well outlined by further drilling and shows that the pool covers only about 800 acres. The sand is 20 to 30 ft. thick, and probably has 5 to 6 ft. of pay. Thus this reserve is not an important one. Several wells were found in Menallen township, Fayette County, where the Big Injun sand has been having a play for the past three years, but the activity there is much less than a year ago. Oil On the west side of the Bradford sand gas pool, Cowanshannock township, Armstrong County, a well was drilled which flowed 100 bbl. the first day from the Tiona sand. The probability is that this well is a freak, as the Tiona has been drilled within a fairly close distance on every

Jan 1, 1940

By John T. Galey

In all, 210 wellst were completed in southwestern Pennsylvania during 1939, which is 59 more than were drilled during the preceding year. Of this number, 137 were gas wells, which is a considerable increase from the 81 completed during 1938. Only 25 oil wells were completed, as against 28 in the previous year, and 28 dry holes, 6 more than last year. Shallow Development—Gas The increase in the number of gas wells is largely the result of a search for additional gas in Armstrong and Indiana Counties. Although a considerable number of wells were drilled in the latter county, the majority of them produced less than 100 M cu. ft. initial open flow. In Armstrong County, a new pool was opened in Cowanshannock township, producing from the third Bradford sand. Several large wells were obtained there, one of which produced an initial of nearly 12 million cu. ft., with a reservoir pressure of 1100 Ib. However, the productive area has been fairly well outlined by further drilling and shows that the pool covers only about 800 acres. The sand is 20 to 30 ft. thick, and probably has 5 to 6 ft. of pay. Thus this reserve is not an important one. Several wells were found in Menallen township, Fayette County, where the Big Injun sand has been having a play for the past three years, but the activity there is much less than a year ago. Oil On the west side of the Bradford sand gas pool, Cowanshannock township, Armstrong County, a well was drilled which flowed 100 bbl. the first day from the Tiona sand. The probability is that this well is a freak, as the Tiona has been drilled within a fairly close distance on every

Jan 1, 1940

By N. L. ALISON

MUCH has been published on the general subject of metal mine ventilation but, so far as I can discover, few specific data on selection of fan equipment to meet the requirements of a given mine ventilation problem are available. This article is intended to point out some of the more important considerations which influence the selection of such equipment. It will be assumed that the mine operator is able to determine the quantity of air which is necessary in the various parts of his mine to produce the required results and the pressure in inches water gage needed to circulate this quantity of air through the mine. There may be instances in which this assumption is not justified, but the fact remains that, with proper engineering talent, these data can be approximated sufficiently close for practical purposes.

Jan 1, 1930

By Elmer A. Jones

Like the caboose on the end of a long freight train L made up of mineral and metal processing and consuming industries, the mining industry progresses according to the movement of the train to which it is coupled. Sometimes the caboose rolls smoothly; occasionally it bumps along on the ties; almost always it is under criticism from someone for being too small, too large, too expensive, foolishly progressive, or hopelessly out of date. We who ride in the caboose are used to the rough by now, but it is nice now and then to have a bit of the smooth. Last year the train of industrial production rolled ahead swiftly and smoothly, and, except for a hot-box caused by strikes in copper mines, so did the caboose. As is brought out elsewhere in this issue, the outlook for 1956 is for more of the same.

Feb 1, 1956

By R. D. Pehlke, J. V. Gluck, R. L. Louvet

A study has been made of the effect of small additions of bismuth on the activity of zinc in dilute solution in molten tin. Free-energy interactions have previously been determined between zinc and various third elements where the solvents were molten bismuth or molten lead.'-4 In both of these solvents, the activity of zinc exhibits a strong positive deviation from ideal behavior (at 550°C y° for zinc in lead is 11.4 and for zinc in bismuth is 3.0). The present work, using tin as the solvent, is an extension to a case where the positive deviation is considerably diminished (y°Zn at 550°C is 1.63). Several previous investigators have studied the Zn-Sn binary system; however, little data is available in the range below 0.1 mole fraction zinc.5= Previous high-temperature galvanic cell studies in the Sn-Zn-Bi ternary system included the determination by Gluck and Pehlke of interactions in the bismuth-rich corner1 and separate investigations of the central region by Oleari and Fioriani6 and by Ptak and Moser.7 Yokokowa et al.8 conducted Knudsen effusion studies in the central region; however, their experiments at 625°K were conducted somewhat below the present experimental temperature range. Their results indicated an increase in zinc activity with the addition of bismuth. The present series of experiments was conducted in galvanic cells represented as follows: Zn Zn++ in LiCI-KC1 eutectic Zn + Bi in Sn (pure reference (fused salt electrolyte) (molten alloy) standard) The experimental apparatus. a multi-electrode system employing alumina crucibles and contained in a Vycor tube under a helium atmosphere, has been described previously, as have been the experimental procedures, precautions, and the methods of data reduction.1-4,- The experimental measurements were made over the range from 450° to 650°C. Between thirty and forty measurements were made in each run. The linearity of the electromotive force vs temperature relations was verified by linear regression techniques. The correlation coefficients exceeded 0.99. The experimental results summarized in Table I include the interpolated electromotive force at 550°C and the temperature dependence of electromotive force. Only results from stable and consistent cells containing more than 0.025 mole fraction zinc are reported. Attempts to run cells at 0.01 or 0.02 mole fraction zinc were not satisfactory. This is attributed to the closeness of the free energies of formation of the chlorides of tin and zinc. Calculations employing Wagner and Werner's criteria for displacement reactions10 indicated that reduction of the zinc content to 0.01 mole fraction places the cell near the borderline concentration for a 1 pct error in measured potential. The compositions shown in Table I are the actual weighed-in amounts. Previous experience has indicated that compositional changes during the running of a stable cell are negligible.' Over the range of compositions studied for the binary alloys, the activity coefficient of zinc was essentially constant indicating that Henry's law is followed to 0.05 mole fraction zinc. The temperature, OK, de-

Jan 1, 1969

By F. O. Garrabrant

POWER is furnished to the Climax Molybdenum Co. by the Public Service Co. of Colorado over two 100,000-volt line to a bank of three 3333-kva. Transformers 100/13.8 kv. These transformers arc so designed that with the addition of forced cooling their capacity may be increased 33 1/3 per cent at 12,000-ft. altitude. Under present conditions, these transformers are operated at 140 per cent of their rating with forced air cooling. On the secondary side of this bank there is a 15-kv., 1200- amp. Westinghouse oil circuit breaker provided with automatic reclosing relays allowing three successive short circuits before lockout. From this breaker 13.8-kv. power is transmitted to a central switching station (Fig. I) where all circuits radiate to the different operations of the property. Each circuit is protected by a 23-kv., 600-amp. oil circuit breaker with by-pass and isolating disconnecting switches. MINE Power at 13.8 kv. enters the mine through a ventilation raise over a three-conductor, size 1-0 varnished cambric insulated, leaded, steel-wire armored cable, insulated from 17 kv. This power is received and distributed through one switching station and four underground substations, shown in Fig. 2. No. 370 substation (Fig. 3) contains three 250-kva, 13,800/440-volt, single-phase Pyranol transformers protected on the high-voltage side by a 600-amp. manually operated oil circuit breaker. This station serves 20 slusher-hoist motors, a 45-kw., three-phase, 220-volt electric furnace, a Massco hot miller for tempering and milling Timken detachable bits and a hoist with 175-hp. motor on the No. 3 development shaft. Also at this shaft are three pumps. One two-stage pump, 1200 gal, per min., 100-ft. head, 3600 r.p.m., driven by a 150-hp. motor, is at the bottom of the shaft. Two deep-well pumps, 500 gal. per min., 500-ft. head, are at the collar of the shaft. Under normal operation the one pumping 1200 gal. per min. is controlled by a float switch to take care of the water. If this pump fails, or if its capacity is insufficient, the first 500-gal. pump is automatically started, and if still more capacity is needed the second 500-gal. pump automatically starts. Time delay relays are provided on the deep-well pumps, so that if power fails the column will have time to drain before the pumps restart. On failure of any of these, an alarm is sounded in the train dispatcher's office, so that mechanics can be sent to ascertain the cause of failure and make repairs. The cable from No. 370 substation is run to the switching station, in which are four15-kv., 600-amp. direct-current solenoid-operated oil circuit breakers. The current for operating and tripping is furnished by a 125-volt storage battery. All breakers are operated from the switchboard in the compressor room. One circuit from this switching station goes to the

Jan 1, 1944

The Raymond Memorial Volume, which the Members of the In-stitute have been so anxiously awaiting since the beloved man's death, is nearly ready for publication. It will contain about 45,000 words and some illustrations and a frontispiece portrait. This book promises to fill every expectation of the contributors to the volume and the host of admirers of the genius who so long guided the destiny of the Institute. It will contain one of Doctor Raymond's best stories, entitled "James and Jim;" his famous article on "Job on Mining;" and one of his poems entitled "The Grand Canyon." A biography of Doctor Raymond has been written by his daughter, who is the wife of a member of the Institute. The memorial addresses delivered by Dr. Henry F. Drinker and T. A. Rickard at the annual meeting in New York in 1919 will be included. There will also be very interesting reminiscences by H. M. Howe, A. S. Dwight, C. W. Goodale, R. W. Hunt, Lyman Abbott, J. F. hemp, T. A. Rickard. The volume has been edited by T. A. Rickard, which promises all that can be wished for the volume from a literary standpoint. The edition will he limited so that it is very desirable that orders for this volume be sent in to the Institute as promptly as possible. The price will be $5.00.

Jan 12, 1919

By ELTCENE A. WHITE

WE are all interested in our ou7n lines of endeavor and consider ourselves the center of the universe. The farmer thinks he is the most important man because he feeds us. The doctor knows he is the real center because he keeps us well. The lawyer says that he is indispensable because he keeps the peace. The banker furnishes us a place to keep our money and tells us how to make proper use of it. The miner sags that without metals there would be no civilization. I think that my branch has sufficient interest and exhilaration. of accomplishment to fully occupy any man's mind and attention. Mining and metallurgy are as old as the human race. It did not have much, if any, importance in the stone age as there are not found remains of iron and copper, but in the bronze age, which was co-existent with the stone age, it came to the front. Iron and copper were the most important metals. Copper, as bronze, was known in ancient Egypt, I\~:IS important in Rome and other parts of Europe and in Asia; in South America among the Aztecs and farther North were the Mound Builders and the early inhabitants of Lake Superior. At a very early date the Egyptians conquered the Sinai peninsula for the sake of the copper produced there. The history of copper metallurgy can be compared to that of a flower. The seed is sown in darkness and in the Dark Ages the crude metallurgy of copper began. As the shoot comes up from the seed it may be compared to the age of alchemy; the branches of the plant can be compared to the Middle Ages; the flowering shoots to the 17th century, the budding to the 19th and the blossom to our own time from 1870 on.

Jan 1, 1930

By Frederick Prime

The first catalogue of Geological Reports of the United States was prepared by Prof. 0. C. Marsh, and published in the American Journal of Science and Ark for 1567, vol. xliii, second series. Since then the list has more than doubled, and it was thought that the publication of a new catalogue, brought clown to date, would be useful to many of the members of the Institute of Mining Engineers. The compiler will be most thankful to have any omissions or inaccuracies in the list sent to him, to be published as a supplement in the next volume of the Transactions. Especially to have the correct title, number of pages, plates, and maps of any volume on the list to which an * is prefixed, as he has been unable to personally consult such works. A preliminary list was issued last February, which has been almost doubled by the kindness of many friends. The writer desires more especially to express the obligations he is under to the following gentlemen : The Chief of Engineers, U. S. A.; Principal Dawson, Mr. G. M. Dawson, Drs. R. J. Harrington and T. Sterry Hunt, of Montreal; Mr. H. Engelmann, of La Salle, Ill.; Dr. F. V. Hayden and Prof. J. W. Powell, U. S. Department of the Interior; Prof. E. W. Hilgard, University of California; Prof. Henry Y. Hind, Windsor, N. S.; Prof. C. H. Hitchcock, of Dartmouth College; Mr. Henry A. Holmes, State Librarian, Albany; Maj. Jed. Hotchkiss, Staunton, Va.; Prof. W. C. Kerr, Raleigh, N. C.; Dr. J. S. Newberry, of Columbia College ; Prof. W. H. Pettee, of the University of Michigan ; Dr. Samuel H. Scudder, Prof. N. S. Shaler, and Prof. J. D. Whitney, of Harvard College; Mr. Sanderson Smith and Prof'. J. J. Stevenson, of New York; Mr. Addison Van Name, of Yale College, and Lieut. Geo. M. Wheeler, U. S. Engineers.

Jan 1, 1879

By B. M. Burchfiel

CALIFORNIA possesses such an abundance of ceramic materials other than clays, that she is quite independent of other states and foreign countries so far as these materials are concerned. Certain users import some feldspar, silica, and allied minerals, but they do so from choice and not necessity. Production is largely for home consumption, so the total volume of ceramic materials produced is comparatively small. Many small deposits of the materials here under discussion are worked by individuals, and their output sold to individual grinding companies or users. The data given here shall be confined to the larger deposits and developments because they give a truer picture of typical deposits, operations, and materials.

Jan 1, 1936

J. E. JOHNSON, JR., New York, N. Y. (communication to the Secretary*).-The discussion of Mr. Henrich's paper took place at a meeting from which I had the misfortune to be absent, and has just come to my attention. I do not wish to let the subject pass without contributing to it a little information which has come into my possession. In 1912, I published a brief note in the Transactions on The Effect of Alumina in Blast-Furnace Slags, giving in tabular form three typical slags used in iron blast-furnace practice, one of them the high alumina slag of, which Professor Richards speaks. That table is reproduced herewith. TABLE 1.-Composition of Slays. 1 3 3 4 5 6 7 CaO by Neutral Ratio Ratio Ratio Al2z03, SiO2, Differ- Substan- Cat Ca0 a A1203 Ratio Per Per ence, ces, CaO Cent. Cent. Per Per Al2O3 + Sioz Sit: SiO2 Cecil_ Cent. Virginia practice 6.5 36.0 54.0 3.5 1.27 1.6S 1.50 Lake-ore practice 13.5 33.0 50.0 3.5 1.08 1.92 1.51 Special experiment... 36.0 24.7 36.8 3.5 0.59 2.90 1.44 It supplies what seems to me convincing evidence that, for the purposes of the iron blast furnace, alumina can be regarded only as a neutral substance, dissolving in the slag and materially altering its viscosity, but not affecting its chemical activity. In subsequent experience with charcoal furnaces, I found the same rule to hold; that the chemical effect of alumina could be disregarded, providing the ratio of the lime and magnesia to the silica were kept constant. This is exactly the experience which Messrs. Dwight and Mathewson had in copper- and' lead-smelting furnaces. I have never seen any evidence or argument adequate to support the contention of Professor Richards-that the alumina acted as a base in the charcoal iron furnace and as an acid in the coke furnace, and that the function of alumina in iron-furnace slags is inherently different from that in copper- and lead-furnace slags-and I am compelled to differ absolutely with his conclusions in that respect.

Jan 9, 1917

By James W. Malcomson

The Tigre Mining Co. of Mexico, owned by the Lucky Tiger Combination Gold Mining Co. of Kansas City, decided early in 1910 to enlarge its mill, which consisted of a concentrator milling 3,000 tons of ore per month. The enlarged plant was designed to crush and concentrate 6,000 of ore and to cyanide 7,500 tons per month. The extra tonnage cyanided was to be obtained from tailings which were stored below the old mill. Power was supplied to the old mill from four boilers; a 150-h-p. Corliss engine and two Weber 60-h-p. gas-engines using producer-gas made from charcoal. The total horse-power required, including 60 h-p. used for machine-drills in the mine, was approximately 275. Cord-wood cost $4.32 per cord, 8 by 4 by 3 ft., and charcoal $15 per ton. The fuel supply in the surrounding country was approaching exhaustion; more than 150 mules and 50 men were engaged in cutting and transporting this fuel, and the unsettled political conditions in Sonora were such that it would be practically impossible to keep an organization of this kind together. The price of fuel was steadily rising and at times it became almost impossible to get sufficient fuel to operate. It was estimated that the enlarged plant, together with the mine, would require 750 h-p., as follows: Horse-Power. Old mill, which was left unchanged,..............180 New concentrator,.......................90 Cyanide-plant,........................380 Mine and other requirements,................. 100 Total,........•..................750 In a study of the best manner to obtain power the following alternative propositions were considered:

Jan 1, 1914