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By Alexander B. Morris

Studies such as the investigations into the solubility of gases in crude oil under various conditions, which have been carried on during the past three or four years, are very interesting from an academic point of view, but this consideration alone is hardly sufficient to warrant the large contributions from the industry necessary to maintain them. Some definite benefit to the industry as a whole should be forthcoming. The purpose of this paper is to direct the attention of company engineers, and company executives, to some of the ways in which the information gained from these studies can be made directly profitable. This work has two principal economic aspects. One affects the investment budget, and through it the financial requirements of the companies. The other affects operations, and through this course is reflected in current earnings. It will be shown that, as a direct result of the investigations into gas solubility, undertaken in the recent past by various investigators, it is now possible: 1. To determine more accurately the amount of reservoir oil originally present. 2. To obtain closer control on operating conditions, to effect more economical recovery. 3. To predict earlier and more dependably when and how much surface lifting equipment will be needed. 4. To reduce, or entirely avoid the very large investment in gasoline recovery equipment now frequently found necessary. 5. To control the gravity of the pipe-line oil so as to secure the greatest possible revenue from the products of the well. 6. To effect the recovery of a large amount of gasoline now wasted while the practicability of a gasoline recovery system is being decided. 7. To plan operations, by comparison with the history of old properties operated without this new information, so as to avoid the mistakes of ignorance made in the past. These points will be discussed in the following pages, though not necessarily in the order stated. There is so much overlapping of the points themselves, and of the data from which they have been drawn as conclusions, that to treat them in any particular order would require

Jan 1, 1935

By A. H. Larson, T. P. McNulty

RECENTLY, an investigation of the absorption of sulfur dioxide gas in molten binary copper alloys was conducted. A Sieverts-type apparatus, consisting of a mercury-filled gas dispensing buret and a mercury manometer, was used initially for determining the volume of gas absorbed as a function of pressure. The equilibration behavior of the alloys studied indicated that the mercury in the gas measuring system was absorbing sulfur dioxide. Owing to the widespread use of mercury as a displacement medium in absorption studies, an investigation was made to determine the nature and magnitude of the mercury - sulfur dioxide absorption effect. The gas measuring system was modified by substituting a Worden Quartz Products Type PDHV fused-quartz-spiral pressure gage for the mercury-filled dispenser and manometer. The dispensed gas volume at known temperature and atmospheric pressure was measured by evacuating a Pyrex vessel of known volume and by admitting sulfur dioxide into the vessel until the attached quartz pressure gage registered atmospheric pressure. Atmospheric pressure was measured concurrently with a separate mercury barometer. The volume of the empty sample chamber and its attendant apparatus was determined by measuring the equilibrium pressure accompanying the addition of a measured volume of sulfur dioxide into the initially evacuated system. The volume of the mercury sample was calculated from the density of mercury at the temperature of the study (25°C). Measured volumes of sulfur dioxide were then dispensed into the system and the equilibrium pressure accompanying each gas addition was determined. From the difference between the system volume and the mercury volume, the number of moles of gaseous sulfur dioxide remaining in the system at each pressure was calculated. The difference between the number of moles of gas dispensed into the system, denoted Enso2: and the number of moles of gas remaining in the system after absorption equilibrium had been attained, denoted nso2(g), was equal to the number of moles of absorbed gas, denoted nSO2. The number of moles of absorbed gas was then converted to absorbed volume, denoted VSo2, in cu cm at stp conditions of (PC and 760 mm Hg. Table I contains calculated values of Snso2, nSo2(g), and VSo2 for different sulfur dioxide pressures. In the original system, denoted Run I, volume limitations of the gas dispensing system prevented absorption studies at equilibrium pressures near atmospheric pressure, so a different gas dispensing system, denoted Run 11, was used for determining the last pressure reading in Table I. The data in Table I are expressed in terms of the absorption of sulfur dioxide in 49.68 cu cm of mercury. In Fig. 1, these data are expressed in terms of the absorption of sulfur dioxide in 100 cu cm of mercury. Since the absorption data plotted in Fig. 1 show a linear relationship, the volume of sulfur dioxide absorbed in mercury is a function of the first power of pressure. The absorption reaction is So2(gas) = SO2 (in Hg) The first-power pressure dependence, coupled with the fact that the sulfur dioxide could be removed from the mercury by applying vacuum, indicated reversible

Jan 1, 1967

By J. H. Brophy, S. J. Michalik

A constitution diagram for the system Mo-Ir has been determined. The maximum solubility of iridium in molybdenum is 16 at. pct at 2110ºC and decreases to less than 5 at. pct at 1500°C. The solubility of molybdenum in iridium is 22 at. pct. Three intermediate phases appear in the system: 8 MoJr, having the p-tungsten structure; a phase, a cornplex tetragonal structure; and the hcp ? phase. Metallography, melting point determinations, X-ray diffraction and fluorescence, and electron micro-probe unalyses were employed in establishing the diagram. PREVIOUS to the present investigation, the intermediate phases in the Mo-Ir system were identified, but no detailed account of the phase diagram has been reported in the literature. Raub1 investigated alloys of Mo-Ir over an extensive range of composition between the temperatures of 800º and 1600°C. The in-termetallic compound MosIr was found to exist with nearly pure molybdenum, as the solubility of iridium in molybdenum was not detectable parametrically in this temperature range. MO3Ir was found to be iso-morphic with a ß-tungsten type structure, having a parameter of 4.959Å. An intermediate hcp phase, designated as the ? phase, ranged in composition from 52 to 78.5 at. pct at 800ºC, and from 41 to 78.5 at. pct Ir at 1200°C. Parameters noted for the ? phase were as follows: at 42.7 at. pct Ir, a = 2.771i0, c = 4.4366, c/a = 1.601; at 78.5 at. pct Ir, a = 2.736A, c = 4.378A, c/a = 1.600. Molybdenum was found to be soluble in iridium up to 16.5 at. pct Mo (83.5 at. pct Irj, with the parameter of iridium increasing to 3.845A at the solubility limit. Knapton,2 who investigated alloys between 15 and 85 at. pct Ir, essentially agreed with Raub's data, but, in addition, found a a phase in as-melted alloys near 25 at. pcto Ir. The oaphase lattice parameters were a = 9.64Å, c = 4.96Å, c/a = 0.515. The a phase was replaced by the 8 -tungsten phase on annealing at 1600°C. Knapton concluded that the a was stable only at elevated temperatures, and placed the composition of the a phase at approximately 30 at. pct Ir. The intermetallic compound Mo3Ir, with a lattice parameter of 4.965A, was included among the 8-tungsten structures reported by ~eller.' Matthias and Corenzwit,4 and Bucke15 studied the superconducting nature of MosIr, and reported a superconducting transition temperature of 8.$K. The present investigation describes the phase relationships in the Mo-Ir alloy system determined by melting point measurements, X-ray diffraction and fluorescence, and metallography. EXPERIMENTAL PROCEDURES Alloys for the determination of the phase diagram were prepared from powders. Commercial 99.9 pct Mo from Fansteel Metallurgical Corp. and 99.9 pct Ir powder from J. Bishop and Co. Platinum Works were used. The powders were weighed to nominal compositions, mixed, and then pressed, without binder, into compacts weighing 4 to 6 g. These were presintered in uacuo between 1200' and 1400°C for 1 hr, to reduce the degree of spattering during subsequent arc-melting. The compacts were arc-melted in a nonconsumable tungsten electrode furnace six times on alternate sides on a water-cooled copper hearth in an atmosphere of zirconium-getter ed argon at 500 mm of mercury pressure. In almost all cases, this procedure yielded buttons of satisfactory homogeneity. The composition of all melted buttons were confirmed by X-ray fluorescent analysis using the experimentally determined ratio of the iridium La1 line intensity to that of the molybdenum Ka1 line as a function of composition. In this determination four alloys analyzed by wet chemical methods were used as standards. An uncertainty range of ±1 at. pct has been attributed to all indicated compositions. All heat treatments and solidus measurements were carried out in tantalum resistance heating elements in vacuum conditions of 10-4 to 10-5 mm of mercury. A detailed account of this procedure has been reported by Schwarzkopf and Brophy.8 In the heat treatment and solidus measurements of iridium-rich alloys (50 at. pct Ir or greater), a tungsten lining was inserted into the tantalum resistance heating element because of a eutectic reaction which occurs between iridium and tantalum at 1948ºc.7 Heat treatments and solidus measurements carried out at compositions less than 40 at. pct Ir both with and without tungsten linings within the resistance

Jan 1, 1963

By V. Rajaram

The oil shales of the Green River Formation in the United States have been considered as a source of liquid hydrocarbons since 1908, with the first retort constructed in Colorado in 1917. However, it was not until 1944 that the mining characteristics of oil shale were investigated in a systematic manner. During the period 1944 through 1956, the Selective Mine and the Demonstration Mine (also referred to as the Anvil Points Mine) were operated by the U. S. Bureau of Mines (USBM) near Rifle, Colorado. Significant progress was made in developing a room and pillar mining method by which oil shale could be mined safely at a very low cost per ton. Mechanical properties of oil shale were determined, safe room spans and roof support techniques were established, and drilling and blasting methods for oil shale were developed. As a follow-on to this USBM effort, a consortium of six oil companies with Mobil Oil Company as project manager carried out a research program during the period 1964-68 at the Mobil mine, located in the vicinity of the Anvil Points mine. Rock mechanics investigations were conducted as a part of this research program, and consisted of laboratory studies, in-situ stress determinations, and roof and pillar instrumentation. This paper will discuss the findings at the Anvil Points mine and Mobil mine to illustrate the stability considerations in underground oil shale mining.

Jan 1, 1983

By R. R. Byran, M. H. Kuryla

The Compania de Real del Monte y Pachuca started a 10-ton pilot plant in March, 1906. The distinctive features of the first cyanide installations at Pachuca were: grinding in cyanide solution, all-sliming and filtration of ore in which silver constituted the major value. Loreto started with a 300-ton " all-sliming" plant, using jaw crushers, grinding in stamps, Chilean mills and pebble mills in cyanide solution, concentrating with Wilfley tables and Johnson vanners, classification by cones and Dorr classifiers, intermittent thickening by decantation, mechanical agitation in flat tanks by stirrers and centrifugal pumps, filtration in Butters filters and precipitation by zinc shavings. The "San Francisco" mill No, 1 was contemporaneous, using a rather similar flow sheet. We shall trace the main developlnents in the three large mills of the district to their present practice. Developments in Large Mills of District Crushing and Grinding.—The trend of development in this part of the work has been the same as throughout the milling world; via., all increase in the degree of comminution of the ore in dry-crushing machines, the advance from pebble mill to rock mill and then to ball mill and the elimination of the stamp battery through the encroachment upon its field on the one side by finer dry crushing and on the other by more efficient wet grinding. The single-stage crushing in jaw type crushers, used at the start, has been replaced by two stages; at first, both stages by gyratory type and later the present practice, which is the same in all three mills, consisting of gyratory as primary followed by cone as secondary and delivering a product that may be rated at 56 to 1 inch. Primary wet grinding, at first performed by stamps and Chilean mills, is now by hall and/or rod mills; present practice differing widely in the three mills. Santa Gertrudis uses a 7 by 15 ft. rod mill, San Rafael

Jan 1, 1935

No true conception of the Park City mining district can be obtained without first giving consideration to the part it has played as a consistent producer of mineral wealth. Its position in this regard is almost unique in the annals of a lead silver camp. For over fifty years it has been a continuous producer of lead and silver and for twenty years it has added to the world's supply of zinc. Few camps with its productive history are so little known to the mining fraternity for the reason that its life has never been punctuated by periods of "boom" which serve to attract general attention, neither has it been the field of operation for promoters who temporarily focus attention upon their scene of action. Its history is one of legitimate mining operations. These were at first carried on by a number of smaller companies. A period of consolidation followed and at the present time the entire production of the camp is in the hands of two major companies and one smaller company. These are flanked by a number of prospecting properties, which are at this time actively engaged in the search for ores and later events will doubtless put some of them in the producing class.

Jan 1, 1925

By Robert J. Willard

The scanning electron microscope (SEM), became commercially available in 1966. Embodying some unique features not provided by conventional electron microscopes, this new electron-optical instrument offers the scientific community a new way of observing the surfaces of materials. In rock mechanics research, the SEM should prove a useful basic tool in characterizing rock fracture on a very small scale and thus contribute to a better understanding of rock behavior at larger scales. This article presents one example of how the SEM is being applied to such research at the Twin Cities Mining Research Center operated by the U.S. Bureau of Mines in Minneapolis. This research center conducts theoretical and experimental studies on a broad range of mechanisms that induce disintegration by the application of energy to rock.1 Some of these studies are concerned with the relation of microstructure to rock behavior and are carried out mainly with the petrographic microscope. At the same time, however, the center recognizes that this relation must be studied through several orders of magnitude, from lattice-size units of rock-forming minerals to field-size rock units. The SEM fits this scheme by extending the capability of the petrographic microscope into smaller orders of magnitude. However, because its resolution is limited to about 200 A at 10,000x, the SEM is not capable of resolving lattice-size units, and hence a conventional electron microscope with a much greater resolution capability is necessary at this order of magnitude.

Jan 6, 1969

By M. E. Nicholson

The solid solubility of boron in iron has been determined by saturating iron with respect to FeyB at several temperatures from 870° to 1135 C. In alpha iron the maximum solubility was found to be 0.002 pct B and in gamma iron the solubility varied from 0.001 pct at 915°C to 0.020 pct B at 1165OC. The eutectic and peritectoid temperatures were found to be 1165° and 911 °C respectively and the gamma iron solidus was located approximately at 0.020 pct B. RECENT investigations of boron-treated steels', ' indicate that the solubility of boron in austenite is of the order of 0.003 pct at 900°C. This has led to the general belief that the solubility of boron in a and r iron is considerably less than that indicated by Wever and Muller." Therefore the solid solubilities of boron in a and r iron have been re-determined. The eutectic and peritectoid temperatures were also remeasured and the r-iron solidus was studied in some detail.* In 1929 Wever and Miiller investigated the phase equilibria of Fe-B alloys. Fig. 1 shows the solid solubility region of the Fe-B diagram based on their investigation. They found that boron lowered the A, transformation temperature to 1381 °C where saturated 6 solid solution "which must contain about 0.15 pct B" and "r solid solution containing about 0.10 pct B" are in equilibrium with liquid containing 1.9 pct B. At the eutectic temperature of 1174"C, 7 solid solution was found to contain "about 0.15 pct B." A peritectoid relation was found to exist between a and y iron with an invariant temperature at 915 "C, where the boron solubility in 7 iron was "about 0.10 pct B" and the solid solubility in a iron "did not exceed 0.15 pct B." Although most of their

Jan 1, 1955

The Library of the above-named Societies is open from 9 A.M. to 10 P.M., except on holidays. It contains about 70,000 volumes and 90,000 pamphlets, including sets of technical periodicals and the publications of scientific and technical societies. Members of the Institute, with few exceptions, are forced to spend a portion of their time in localities isolated from sources of information. To these the Library, through its Library Service Bureau, can render valuable service through correspondence; letters requesting information will receive especial attention. The Library is prepared to furnish references and photographic copies of articles on mining and metallurgical subjects; to determine the existence of mining maps, and to furnish general information on the geology and mineral resources of all countries. All communications should be made as definite as possible so that the information received may be what is desired and not include collateral matter which may not be of interest. The time spent in searching for such collateral matter will be saved, and the information will be sent more promptly and in more usable shape.

Jan 7, 1917

By EL HANAF

The exploratory program initiated in Egypt in 1937 by four major oil companies was well under way early in 1939. Extensive gravity-meter surveys were carried out in the Sinai Peninsula and the Eastern and Western Deserts. Seismic and magnetometer work vas conducted on a restricted scale. The data collected justified wildcat drilling on structures located geophysically and/or geologically.

Jan 1, 1946

By N. O. Johnson, J. Boyer, D. H. Sargent, R. B. Frahme

Although the Western bentonite industry has grown rapidly, it is facing major challenges to sustained growth. The fundamental penalty of costly overland transportation to both domestic markets and to US seaports is of increasing importance; as both substitute materials and foreign bentonites present more formidable competition in the historic market areas of drilling muds, foundry sands, and iron ore pelletizing; and as foreign demand grows more rapidly than domestic demand. The Western bentonite industry is facing these challenges by altering its transportation patterns, by upgrading of products, and by emphasizing customer service and stringent quality control.

Jan 9, 1979

By J. A. Grimes, Paul Billingsley

A. Introduction. 1. Association of Ores and Igneous Rocks. 2. Identity of Granite Rocks. B. General Geology. 1. Geologic Events of the Igneous Cycle. 2. Association of Igneous Intrusions with Tectonic Forces. C. Igneous Rocks. 1. Andesite Period. 2. Granite Period. (a) Diorite. (b) Quartz-Monzonite. (c) Aplite. (d) Quartz-Porphyry. (c) Quartz-Veins. 3. Rhyolite Period. 4. Comparative Analyses. D. Classification of Deposits. 1. Genetic Classification. 2. Parallelism Between Igneous Stages and Stages of Ore Deposition. Part 2.—The Ore Deposits Andesite Period. A. Andesite Phase. 1. Disseminations—Baggs Creek. 2. Contact Deposits—Iron Mines of Ekhorn Mountains. 3. Fissure Veins—Emery District. (a) Fissure Veins in Andesite Walls. (b) Mineralization Along Bedding of Flows. (c) Mineralization of Amygdaloidal Lavas. (d) Mineralization of Breccia. 4. Summary.

Jan 1, 1918

By J. E. Johnson

Discussion of the paper of Bradley Stoughton, presented at the Cleveland meeting, October, 1912, and printed in Bulletin No. 71, November, 1912, pp. 1245 to 1275. J. E. JOHNSON, JR., Ashland, Wis. :-Is it true that titanium reduces the chill in chilling iron? If so, as I think Mr. Stoughton has stated elsewhere, then I do not see how titanium is beneficial in car-wheel mixtures. One of the most difficult things to do is to get a proper chill and a proper degree of toughness, and the goodness of an iron of the given composition for charcoal-iron purposes is denoted by the chill which it will take as compared with its composition. If titanium reduces that chill, then it does not seem to me as good for car-wheels as its absence would be, and I should like to have it explained what effect titanium has on the chill of a given iron. MR. STOUGHTON : It is true that titanium reduces the chill of iron quite noticeably, yet, at the same time, if I am correctly informed, 90 per cent. of all chilled-iron rolls are made to-day with the titanium treatment, and a great many car-wheels, but one has to make changes in the silicon added and also, if I am correctly informed, in the manganese. The advantage of titanium is that when the proper changes are made, so that we get the same depth of chill with the titanium as we otherwise would without, the chill is much harder than before, and also the body of the roll or wheel is tougher and somewhat stronger, especially under shock. JAMES F. KEMP, New York, N. Y.:-This subject is obviously one of great importance to the iron industry, in that if we call find a method of using titaniferous ores, we will prolong the life of our iron reserves. Fifteen or more years ago, primarily from the study of the ores in the Adirondacks, I be-

Dec 1, 1912

The sum of $100 was appropriated to the War Minerals Committee for expenses of letter paper, postage, etc. The report of the Treasurer was accepted and ordered filed. Upon the recommendation of the Committee on Membership, sixty-eight Members, two Associate Members, and ten Junior Members were elected. The Secretary presented a letter from the office of the Chief of Ordnance, U. S. A., offering him a commission in the Ordnance Officers' Reserve Corps, and asking him to submit to the governing body of the Institute a request for release from his contract with the Institute, in order that he may accept the commission in question. The following minute was then passed. "The Executive Committee is of the opinion that the Secretary of the American Institute of Mining Engineers can be of more use to the Nation in his present situation, in view of the fact that there is no possible substitute for him in this position, than he could be if he left to accept a commission as an officer in the Ordnance Department, and this Executive Committee requests that an executive officer of the Institute go to Washington and confer with the Chief of Ordnance, requesting a withdrawal of the offer to the Secretary of the Institute and presenting the names of substitutes therefor." The payment of 'a special clerk for the Committee on Increase of Membership at the rate of $100 a month was ordered continued for a further period of six months.

Jan 10, 1917

By J. A. Roberson, Robert A. Rapp

From the observation of platinum wire marker movement in the oxidation of columbium at high lemperatures and low oxygen pressures, predonzinant cation diffusion in CbO, has been demonstrated. The Cu,0 molecule was used as an oxidizing species to study the nature of the porous scale and the location of the reduction site in the oxidation of colum-bium. The Cb205 scale contains microporosity and forms by alternate ionic diffusional growth and fracture. The oxidation of columbium at high temperatures and very low po, results in a relatively compact and protective Cb205 layer. THE observation of marker movements during oxidation is one means for the identification of the mobile ionic species in an oxide lattice. Previous marker experiments in the oxidation of columbium have all resulted in the markers being found on the outside surface of the Cbz05 scale. The Cr203 powder markers of Klopp et a1.,' the gold film marker of Kofstad and ~jijllesdal,' and the platinum wire marker of Cathcart et a1 .3 were found at the oxide/gas interface for oxidation temperatures ranging from 450" to 120O0C. However, in all experiments relatively high oxygen pressures were used. As discussed by Mrowec, even the interpretation of marker experiments in simple scales containing only one compound is not without ambiguities. In brief, it can be said that a marker may be found almost anywhere in the scale layer if the metal oxidizes by cation diffusion through the scale; the position of the marker depends upon morphological happenings in the scale. When considering marker movement in a polyphase scale one must proceed with extreme caution. For example, in the past (and present) work markers have never been found at the columbium-scale interface, and one might infer that the oxygen ion is mobile in CbO and CbO,. However, only trace quantities of CbO and CbOz have been present on any of the specimens, so no firm statement is justified on this basis. Despite previous experimental work, considerable doubt still exists concerning the role of the oxides CbO and CbOz in the oxidation of columbium. The identification of the mobile ionic species in CbO and CbOz from the observation of platinum wire markers was one goal of the present investigation . The linear kinetics of columbium oxidation at high temperatures (T - 1000°C) suggests that the Cbz05 scales which form on columbium are porous. From mercury absorption measurements on a Cbz05 scale formed at 500"C, Aylmore et al.' reported a minimum volume fraction of connected voids equal to 0.15. While these scales often appear to be quite porous when viewed in metallographic cross section, they are so brittle that metallographic preparation is likely to exaggerate any porosity originally present. In this investigation, porosity developed during the oxidation of pure columbium and present at the high temperature was detected by oxidizing specimens in sealed evacuated capsules containing large compacts of mixed copper and CuzO powders. wooda has demonstrated that the CuzO, or (CuzO),, molecule is volatile and that oxygen is transferred by the CuzO molecule from a Cu/CuzO mixture to materials having a greater affinity for oxygen. For each molecule of CuzO that is reduced at a sink for oxygen, two atoms of copper are deposited. Quantitatively, essentially all of the oxidation carried out by a Cu-Cu20 compact results from a displacement reaction involving the CuzO molecule. When a metal which oxidizes to form a porous scale is exposed to the CuzO vapor, the CUZO molecules are reduced in the pores leaving a deposit of metallic copper to mark the site of the reduction. This technique has the rather unique advantage that any copper-coated pores found in the scale are unambiguously related to the reduction site in the growth of the scale under consideration. Pores or cracks which form in a msition*- external to the reduction site or which occur as a result of cooling or handling of the specimen will not exhibit the copper deposit. EXPERIMENTAL PROCEDURE Marker experiments were made on columbium metal, and on pellets of CbO which had been pressed and sintered. Platinum wire markers (0.001 and

Jan 1, 1968

By Rodolfo V. de la Cruz

The in situ deformability of rock masses is determined by relating the applied load to the radial displacements of points on the borehole wall that are outside of the loaded surfaces. The external displacement method includes the steps in which: a) radial displacement sensors are installed to measure the change in length of a diameter of a borehole; b) unidirectional self- equilibrating pair of forces perpendicular to the direction of radial displacement measurements are applied on opposite sectors of the borehole wall, and; c) using elastic theory, the in-situ deformability of the rock mass can be related with the applied loads and measured radial displacements. The displacements outside the loaded surfaces are comparatively smaller in magnitude than displacements inside the loaded surfaces. These displacements, however, are sufficiently large and can be measured precisely by commercially available linear displacement sensors. Loads are applied by a conventional borehole jack. Existing methods for measuring the in situ deformability of rock masses yields unreliable results due to complex boundary stresses, small and varying contact areas, and the existence of fractures. It was shown that in the external displacement method, the effect of boundary pressure distribution and contact area are negligible. Also, since the displacements measured in the external displacement method were due to materials that are deeper inside the rock mass, borehole fractures have less influence on the calculated deformation modulus.

Jan 1, 1982

By AIME AIME

SECTION DELEGATES were given an opportunity to see how the machinery of Institute administration functions, on Tuesday evening, Feb. 16, when they were the' guests at the regular monthly meeting of the Directors. Of the new board of 25 members, 19 were present at the meeting, including directors from Seattle, Los Angeles, Wyoming, Oklahoma, Chicago and Pitts-burgh, the new junior past-president from Jerome, Ariz., and the new president from .Washington, D. C. The complete list of the 72 in attendance at the dinner,: held in the main dining room of the Engineers' Club, which pre-ceded the general session of the Directors'. meeting, follows:

Jan 1, 1932

By Earl C. Henry

Magnetic iron ore was mined in Essex County, N. Y., during the American Revolution; Benedict Arnold is said to have mined ore near Port Henry to secure iron for chains and spikes for the Lake Champlain fleet. Details regarding the operations prior to 1804 are not easily obtained but work on a commercial scale appears to have been started about 1838. The Witherbee, Sherman & Co. was established in 1849. The property of the district is held in fee almost entirely by the mining companies. The Mineville iron-ore district, as well as the entire Adirondack region, belongs to the pre-Cambrian complex. The readily identified rocks consist of gabbro, anorthosite, syenite, and granite, and are classed as igneous, eruptive, and intrusive. In addition, there is a great variety of gneisses, rocks with a variable mineral composition but all more or less distinctly foliated. The Grenville series are the oldest rocks in the district; this series consists of graphitic white limestones, graphitic sandstones, and quartzites and gneisses with or without graphite. The orebodies occur in the gneissic rocks and are comformable to the structure of the rocks. The typical occurrence of the ore in this district is in lenticular bodies with a parallel pitch to the southwest; this structure is best exemplified in the New Bed mine. The Harmony and Old Bed orebodies are faulted by two sets of diabase dikes, one set having a southwest strike and the other set an east-west strike. The ores occurring in the acid gneissic rocks are non-titaniferous. The ores occurring in the gabbros and anorthosites are high in titanium; these deposits are irregular, have no structural relation with one another, and are unquestionably of igneous origin. The origin of the gneissic rocks and the ores therein contained is not settled; both the sedimentary theory of ore concentration and the igneous theory of magmatic segregation have been advanced. The iron mineral in all the orebodies is crystalline magnetite; some very perfect and large specimens have been obtained. The gangue is

Jan 1, 1925

By Leonard Greenburg, William B. Harris, Gustäv Werner

HAULAGE in tunneling operations generally has been done with electric locomotives. As a rule, on short hauls the source of electricity is a storage battery mounted on the locomotive, which, of course, must be removed and recharged periodically. Where the distance from the recharging point to the tunnel face is very long, and where loads are heavy, trolley-driven locomotives are used. Diesel engines have been used in mining and tunneling operations in Europe for a number of years. The recent reports of studies in Belgium1 and by the Bureau of Mines in this country2-4 have indicated the potentialities of this form of power for haulage, mucking, bulldozing and many other underground operations. The hazards attending the use of Diesel engines in more or less closed spaces have long been known. The exhaust constituents that may create a harmful or objectionable environment are carbon monoxide, oxides of nitrogen and sulphur, carbon dioxide, aldehydes and smoke. Lack of precise information regarding the concentration of these gases and the ventilation requirements to reduce them to safe levels has to some extent suppressed their general acceptance in tunneling and mining work. Not until the work of the Bureau of Mines referred to above, and certain experience gained in the construction of the Delaware Aqueduct,‡ has there been available the requisite information regarding the conditions under which their use may be permitted. This paper concerns itself with the successful operation of Diesel engines underground in the construction of certain parts of the Delaware Aqueduct, and describes the conditions under which Diesel engines have been found to operate with a minimum production of noxious gases. The test data reported were obtained during the operation of Diesel engines over a period of two years.* STUDIES BY THE NEW YORK STATE DEPARTMENT OF LABOR Exhaustive tests were made by the Division of Industrial Hygiene, of the composition of the exhaust gases given off by a Diesel engine mounted on. a test block. These tests showed that certain quantities of the gases are discharged from the exhaust. On the basis of these figures, preliminary requirements of design and control

Jan 1, 1942

By ROBERT E. HARDWICKE

THE QUESTION of whether the production of oil should be limited to market demand has been constantly discussed during the last two years. Oil men, legislatures and courts have reached highly conflicting conclusions. Opponents of limitation to market demand assert that it is a scheme of the big purchasing companies to fix prices and to create a monopoly. Proponents, on the other hand, declare that such a limitation is necessary to prevent physical waste and that the effect on prices is merely incidental. A brief review of market demand legislation will disclose the confusion existing. The laws of Oklahoma,' prohibiting waste of oil and gas, specifically' authorize limitation to market demand as a method of preventink such waste. These laws and the proration orders based thereon have been upheld by the Supreme Court of Oklahoma, by several three-judge Federal District Courts, and by the Supreme Court of the United States.' Kansas has a similar law3 but no case has been found which discusses its validity. About a year ago the California Legislature passed a comprehensive conservation act, generally known as the Sharkey Bill giving authority to restrict production to an amount representing current requirements for use, taking into consideration oil and products in storage. This may be considered as equivalent to limitation to market demand. The Act was defeated upon referendum vote after a hard fought campaign in which it was charged that the Act would result in destruction of the independent operators.

Jan 1, 1932