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By E. H. Kelton

The purposes of this paper are to describe the use of adjustable cut and draw tools as a control test of drawing properties and to point out that no other well-known test or combination of tests determines this quality in zinc and zinc alloys. Rolled zinc has been used for making drawn articles, particularly battery cans, for many years. The development of rolling treatments satisfactory for these purposes followed the usual course of trial and error experimentation depending upon cooperation with customers to determine what type of material was suitable. A quick test of drawing quality was highly desirable, of course. Scleroscope hardness and temperll having no apparent relation to drawing quality, were used simply to check the duplication of rolling treatment and grade of metal. The dynamic ductility1 test, on the other hand, was believed to be so like the drawing operation as to provide a reliable index and came to be taken as the criterion of good drawing properties. Faith in this test was strengthened by the fact that metal having the highest ductility was more satisfactory for operations, such as the manufacture of battery cups, that required several redraws. No distinction was made at that time in specifying metal as to whether it was to be subjected to simple cut and draw, redrawing or forming operations. It developed, however, that in some grades of metal the highest ductility did not coincide with the most satisfactory quality when the material was used for a single draw. When zinc-base alloys, with their wider ranges of effective rolling treatments, came into increased use, their dynamic ductility and drawing quality appeared to have no connection whatever. Furthermore, comparisons of known drawing quality with other physical properties of the metal, including tensile strength, elongation and dynamic cold bends, were fruitless in yielding any clear relationship. Almost any test value produced in one piece of metal could be duplicated by another rolling or annealing treatment with attendant different drawing characteristics.

Jan 1, 1934

By B. A. Eaton, R. H. Jacoby

This paper presents the depletion-performance correlations developed using data from PVT studies and well-completion tests of 27 rich gas-condensate and volatile-oil reservoir fluids. The PVT behavior for each fluid war determined experimentally in the laboratory, and the depletion performance of each fluid was then calculated. Well-completion test data consisting of reservoir pressure and temperature, initial total gas-oil ratio, and stock-tank oil gravity were used with the depletion-performance data to develop general performance correlations. Three correlations are presented. The first equation shows the empirical relation of gas in place per barrel of hydrocarbon pore space with reservoir pressure and temperature, and initial total gas-oil ratio. The second equation is the correlation of stock-tank oil in place per barrel of hydrocarbon pore space. The third equation relates stock-tank oil production (to 500-psia depletion pressure) with pressure, temperature and oil gravity. All three correlations are also presented in convenient graphical form. Gas production to 500-psia depletion pressure is approximately 92.6 per cent of the gas in place for each fluid, so no correlation was developed for gas production. INTRODUCTION The rate of discovery of shallow, low-pressure and low-temperature oil reservoirs in the United States has been declining in recent years. For this reason, the search for oil has gone to greater depths where high pressures and temperatures are encountered. A high-pressure and high-temperature reservoir is the environment in which many rich gas condensates and highly volatile oils are found. Because of this trend, the performance prediction of such reservoirs has become an important task of the reservoir engineer. The need and usefulness of a performance correlation based on field data that are available from the usual well-completion tests have previously been established. These earlier attempts have shown that the phase behavior of rich gas-condensate systems and volatile-oil systems can be correlated with fluid properties, pressure and temperature. However, very little information on gas-condensate depletion performance5 was available at the time of these earlier attempts. The availability of more recent data has made possible the development of an improved correlation. The data, as listed in Tables I and 2, are for 25 gas-condensate and two volatile-oil systems that were studied. The problem was to correlate the data for in-place fluids and the production data with the initial total gas-oil ratio, initial reservoir pressure and temperature, and stock-tank oil gravity. These correlations were obtained by multiple regression analysis, whereby the data were fitted to an equation by the method of least squared error. BASIS OF THE CORRELATIONS 1. The data used in the development of these correlations were obtained from depletion-performance calculations6 and well-test or production measurements. 2. All of the independent variables used in the correlations are available from the usual well-test completion data. 3. The reservoir volume considered is 1 bbl of hydrocarbon pore space (HCPS). 4. The gas-oil ratio used is the total standard cubic feet of gas (at 14.7 psia, 60F) coming off the entire separator train per barrel of stock-tank oil. This minimizes the effect of separator conditions which might vary from system to system. 5. The correlated pressures are the actual reservoir pressures which might or might not be the saturation pressure of the reservoir fluid.

Jan 1, 1966

By H. J. Wasson

At the close of 1927 Venezuela was producing at the rate of 205,000 bbl, per day, making it the third country in the world in point of present daily production. For the year, the total was close to 64,000,000 bbl., representing an increase of about 70 per cent. over the 37,000,000 bbl. in round numbers produced in 1926. All of the 1927 production canie from fields opened up before the beginning of the year. While no new fields were added to the list of shippers, the past 12 months' wildcatting yielded a fair quota of new discoveries which, in the light of prcsent results, may be considered likely sources of production in due time. Altogether three such promising finds were made Of first importance, at least for the immediate future, is the completion by the Lago Petroleum Corpn. of the San Matins well, 4 miles north of the present edge of the Lagunillas field. Although rated as only a 125. bbl. well, at 3217 ft., it indicates a probable extension of the field over the intervening 4 miles between the two. The two other wildcat discoveries of importance were the Los Manueles well in the District of Colon, which has in all probability opened up a new field about 7 miles north of the present Tarra oprations; and the Honibre Pintado well of the Standard Oil Co. of Venezuela,. in the State of Falcon, which is considered to be a promising clc~vc~lop~ncnt. Neither of these last mentioned two discoveries will apprcciably affect production during 1928, as the Manueles area must await the carrying out of a general plan for the exploitation of the District of Colon, a problem requiring time. The Hombre Pintado area is being tested further, but doubtless several wells will be put down before. anything definite will be done towards making the pipe line. arrangements that rnust necessarily precede the commercial exploitation of the field. The San Matias Well The San Matias well is a highly significant dcvelopment,. It is located along the trend of the La Rosa-Ilagunillas producing formations, and when drilling started, production in the Lagunillas field was 4 miles

Jan 1, 1928

By G. F. LOUCHLIN

A FEATURE of the International Geological Congress to be held at Pretoria, South Africa, in the summer of 1929,. will be a symposium on the gold resources of the world. In this connection the U. S. Geological Survey and Bureau of Mines have been asked to prepare a report, showing production in the United States, describing the geology of its principal gold- producing districts, and estimating reserves (a) assuming a continuation of presen6economic conditions, and (b) assuming lower costs. This report will not be completed before April 1, but data thus far assembled are here presented with the hope of profiting by discussion and by information from those well informed on any of the important gold-producing districts. Gold production in the United States rose to a maximum exceeding $100,000,000 in 1915 and then rapidly declined to about $52,000,000 in 1920. Since then it has fluctuated, but on the whole slightly declined. Reviews of the eight leading states afford the following tentative conclusions :

Jan 1, 1929

By AIME AIME

THE Institute of Metals held a well rounded out symposium on the working of metals, distributed over two sessions. At the first session* four papers were presented, two dealing with the, cold working of metals and alloys and two with the hot working of non-ferrous alloys. The first paper by E. V. Crane, dealt with "Metal Working in Power Presses." Mr. Crane pointed out the empirical nature of engineering data available for use in calculating the probable stresses developed and power requirements, for the shearing, drawing, binding and other forming operations. He described the various operations, methods of determining stresses developed and presented data obtained. In the discussion C. F. Hammond took exception to Mr. Crane's objections to the rather too frequent. annealing operations in drawing of cartridge cases, pointing out that the material was-manufactured to meet specified structure and physical requirements, which could only be met by carefully controlled sequences of working and intermediate annealing operations.

Jan 1, 1931

By Joseph A. Holmes

I. INTRODUCTORY. THE plans for the investigation of fuels and structural materials now being conducted by the Technologic Branch of the United States Geological Survey were, before being decided upon by the Director of the Survey, submitted for consideration to the National Advisory Board, upon which there are nine representatives from the membership of the American Institute of Mining Engineers, viz.: Messrs. John Hays Hammond, Robert W. Hunt, B. F. Bush, and E. V. d'Invilliers (representing the Institute); Messrs. Julian Kennedy and C. S. Robinson (representing the Iron and Steel Institute); Dr. Charles B. Dudley (representing the American Society for Testing Materials); Mr. F. H. Newell (representing the U. S. Reclamation Service); and Dr. Richard Moldenke (representing the American Foundrymen's Association). It seems fitting, therefore, that a report of these investigations of the past three years should be submitted to the Institute for publication in its Transactions. The above, together with other representatives of the national engineering societies and allied organizations, were invited by President Roosevelt to serve, along with the Chiefs of the several Government Bureaus who have charge of public works and large. fuel purchases, on the National Advisory Board to give advice concerning these investigations. The appointment of this National Board grew out of a wish on the part of the President, the Secretary of the Interior, and the Director of the Geological Survey not only that the appropriations for these investigations be expended in a manner most beneficial to the several branches of the government

Jan 7, 1908

An ore search for commercial titanium-bearing ore deposits is in progress by the Crane Co., manufacturers of valves, because they expect this metal to be important in valve manufacturing in the future. The company will eventually be mining and making titanium sponge. At present they are buying titanium tetrachloride from the Stauffer Chemical Co, at Niagara Falls and making titanium by reaction with magnesium. Production from the Babbitt concentrator of Reserve Mining Co. is scheduled to begin in late 1951 or early 1952. The capacity is to be 300,000 tons of pellets per year made from magnetic taconite concentrates.

Jan 7, 1951

By John Henry Harden

This shaft, located in the northern anthracite coal-field about 2300 feet southwest from the court-house at Wilkes-Barre, in the County of Luzerne, Pa., is the property of the Lehigh & WilkesBarre Coal Company. The sinking and cribbing to the solid rock (see isometrical view on Plate IX) was conducted by Mr. W. W. Kenrick. Dimensions of the earthwork to the foundation of the cribbing, 51' 2" long, 17' 4" wide, 31' deep. Total amount of excavation in cubic yards, 998.5. Dimensions within the permanent cribbing, 45' 4" long, 11' 16" wide, 31' deep, divided into six parts by buttons 8" x 12", each division, 7' x 11' 6". Permanent cribbing 12" x 12"; temporary cribbing 8" x 10" ; backing, 3" thick ; clay puddle to exclude surface water, 12" thick; conductors, 8" x 5"; lining, 1" thick from top to bottom of the shaft. In the latter part of the year 1871, Mr. H. Murray & Son contracted with the company for the continuation of the work at the rate of four hundred dollars per yard in depth, to a point 100 feet below the Hillman seam of coal; for the succeeding 100 feet the price to be increased twenty-five dollars per yard, and so on until the bottom rock of the Baltimore seam of coal was found. The size of the shaft within the cribbing timbers is 45 feet 4 inches by 11 feet 6 inches, having six divisions of equal dimensions, 7 feet by 11 feet 6 inches, giving room for what is known as the "standard diamond " car, whose capacity when level full is 100 cubic feet, but when loaded by the miner 4 inches above the top contains 112 cubic feet." Two divisions of this shaft are intended for hoisting coal from the Hillman seam, two from the Baltimore seam, one for ventilation, and one for pumps. The works were planned for two pairs of direct-acting, high-pressure engines, twenty-four boilers, and for an estimated output of 2500 tons of coal per day from the two seams.

By Stanly A. Easton

SEVEN years ago there was installed in the hospital of the Bunker Hill & Sullivan Mining & Concentrating Co. at Kellogg, Idaho, an ultra-violet ray quartz lamp, the standard equipment which is found everywhere in the offices of physicians and among usual hospital equipment. The use of this lamp was con- fined largely to treatment of pathological cases, still treatment of under-nourished children, run-down anemic people, both men and women, and, as a general tonic, was part of the routine hospital procedure. At the latitude of the Ceur d'Alene district and especially because of the position of the towns in deep canyons, with much overcast and cloudy weather, sunshine is not plentiful at any time of the year; for many of the winter months there is scarcely any. Underground workers, particularly during the winter, have little sun- shine; it is not unusual to have none at all for weeks at a time. Treatment by the ultra-violet ray lamp in the hospital has resulted in many extraordinary benefits but the use of the lamp is expensive and limited. Some weeks ago attention was directed to the automatic solarium equipment of the Burdick Corporation. The doctors strongly recommended the increased use of the ultra-violet lamp for its curative powers and tonic effects, urging that it be made accessible to all employees. Real interest was . . also displayed by employees with the possibility of securing ultra-violet ray treatment for themselves and families under better conditions than it was possible to have by the limited use of the lamp at the hospital. This resulted in the installation of the so-called sun room or automatic solarium as an adjunct to the mine change-house. An annex was built to the change-house, with dressing rooms for women, children and men from other departments, and the outfit put into use on Sept. 5, 1929. The installation consists of an escalator, or

Jan 1, 1929

By Charles Albert Ashburner

THE stratigraphical geology of the vicinity of Buffalo has always been of great interest on account of its bearing on the origin and history of the Niagara-river gorge, between the Falls and Lake Ontario. Recently, however, the character and thickness of the strata which underlie Buffalo have acquired more practical and economic importance on account of their relation to the possible occurrence of natural gas in commercial quantity near the Niagara river. In a paper presented at the Duluth meeting (l887), on " Petroleum and Natural Gas in New york State" (Trans., xvi., 906), I gave a brief description of the four wells which had been drilled by the Buffalo Cement Company between 1883 and that time. One of these wells is 1305 fret deep; and, at the time that my paper was finally revised for the Transactions (June, 1888), it was still an open question whether the drill in this well had reached the Niagara limestone, or had penetrated the Medina sandstones and shales, which latter are boldly exposed in a number of localities in the district, hut more particularly along the Niagara river in the vicinity of Lewiston and Qneenstown. The difficulty in this geological question at Buffalo has lain in the fact that no reliable determination could be made of the thickness of the strata included between the Corniferous limestone, immediately below which the drilling of the Buffalo gas-wells was commenced, and the Niagara limestone. On the other hand, the strata included between the latter limestone and the middle portion of the Medina sandstones and shales, have been minutely measured and studied in the Niagara gorge below the Falls by many American and European geologists. The first reliable section of these strata was constructed by Professor Eaton, and published in 1824 in his report on the Geological and Agricultural Survey of the District adjoining the Erie Canal. This section, extending from Lake Erie to Lewiston, is complete, with the exception that no thickness is given to the Salina or Onoudaga salt group,

Jan 1, 1889

By H. H. Rachford, J. Douglas, D. W. Peaceman

A numerical solution of equations describing two-phase flow in porous media shows promise in providing a technique for predicting the displacermet from satlds of oil by water or gas. The description includes the influence of relative permeability, fluid viscosities and densities, graviry, and capillary pressure, and, tholrgh tested ortly for two-dimensional cases, should be eqlmlly applicable in three-dimensional geometry. Two memorical methods ore presented: the first method is quite general in its applicability; the second method can be used only with certain types of boundary conditions but requires less computing. Comparisons of computed results with data from Inhoratory models are presented. These data were taken on a water flood of a strarified model and on water floods of a five-spot model for favorable and unfavorable mobility ratios. On the stratified model, excellent agreement with recovery at breakthrough was obtained; agreement with recovery after breakthrough was poor. In the five-spot model, good agreement was obtainecl with recovery at and after breakthrough. The purpose of this paper is twofold: first, to present a reservoir engineering method requiring knowledge only of rock geometry and the normally measured rock and fluid properties for calculating the multi-dimensional flow of water displacing oil from porous, water-wet rock containing connate water; and, second, to investigate the validity of the method by comparing results of calculations with previously observed displacements in laboratory models. The availability of such a verified technique of reservoir analysis would afford major advantages. First, it would demonstrate that the fundamental macroscopic concepts of two-phase fluid mechanics, i.e., relative permeability and capillary pressure, yield an adequate description of the physical process. Also, since most reservoir rocks appear to be water-wet and contain connate water along with oil, it would provide a method of technical and economic value for calculating the course of oil displacement by water directly from measured reservoir and fluid properties. It is important to emphasize that the calculation is subject only to the limitations of detail and precision of reservoir information, but not to limitations introduced by simplifying assumptions. Further, it would providc almost the only means of examining the influence of factors such as the size and extent of reservoir inhomogeneities and uncertainties in the basic reservoir data. Knowledge of this influence is essential in stating quantitatively the detail required to define a reservoir and in establishing the relation between the uncertainty in the definition of reservoir properties and the reliability of predicted performance. Moreover, in the process of solving a particular problem much detailed information would become available about the displacement process. For example, at each point in the reservoir for all stages of the displace ment. the calculations would yield not only the water and oil saturations but also the direction and magnitude of fluid velocities and the local fluid mobilities. Such dctail is potentially of great value in giving insight into the mechanics of particular displacements. The development of such a method has long been the goal of research in the application of numerical an-alysis to petroleum reservoir enginecrinz. The most complete treatment of the displacement process published to date is that of Douglas. Blair, and Wagner,' which, however, was limited to flow in a single dimension. The method presented in the present work is hascd on the numerical solution of a finite difference analogue of the multi-dimensional differential system describing the displacement process. Although current work has considered only displacement of oil by water from water-wet sands, the differential system for other immiscible displacements, such as gas displacing oil with which it is in phase equilibrium, is quite similar. It should therefore be expected that the technique described will be applicable to displacement by gas as well. The description of the simultaneous flow of fluids through porous media in terms of relative perrncability and capillary pressure has been adequately discussed in the literature and standard textbooks. Sec, for exampje, Muskat. Chapter VII.'

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Jan 3, 1918

By A. Becker, J. A. Slankis

Equipment has been developed to utilize natural 8 Hz electromagnetic fields to measure rock resistivities. Telluric and magnetotelluric surveys have detected resistivity variations associated with geological contacts and metallic sulfide deposits. The fundamenfa1 premises of these methods are illustrated by the results of surveys across a Pleistocene-Precambrian contact in the Ottawa Valley and a near-surface sulfide deposit in Northern Quebec. Such interfaces are characterized not only by variations in apparent resistivity, but also, unexpectedly by the spatial anisotropy of the electric fields and the presence of a strong vertical magnetic field component in their vicinity. Standard geophysical electrical and electromagnetic methods (Heiland, 1940) for the determination of the electrical properties of the ground and the search of good electrical conductors necessitate the use of a transmitter and receiver which are coupled galvanically or inductively through the ground. The electrical properties of the ground are deduced from either the transfer function, or the impulse response, of the transmitter — ground — receiver system. Where deep penetration is desired these methods require powerful transmitters whose weight and size increase the cost and reduce the speed of operation. It is possible however, to resort to another class of electrical prospecting methods which employ ambient, natural electromagnetic fields in place of a transmitter.'-' In the audio and subaudio frequency ranges, these fields are generated by thunderstorm activity. At some distance from the seat of the disturbance, the e.m. fields propagate as plane waves with a horizontal magnetic field component. The incident wave, of course, induces currents in the ground. Where the ground is homogeneous the relation between the horizontal magnetic and horizontal electric fields vectors is particularly simple:' /E/ = \[SpT/H/ (1) where: /E/ = magnitude of horizontal electric field in millivolts/kilometer (RMS) /H/ = magnitude of the orthogonal inducing magnetic field in milligammas (RMS) p = rock resistivity in ohm-meters i = frequency of measurement in c/s In practice, the ground is seldom an homogeneous half space, lateral conductivity variations exist, (in the case of base metal prospecting these are the features actually sought) and the two field vectors are no longer simply related. The ratio of E to H is still useful, however, for the determination of an "apparent" ground resistivity. From a theoretical view point, the general problem of a two dimensional fault or dyke anomaly can be separated into two distinct cases. In the first case, where the e.m. energy propagates in a direction normal to the strike, the horizontal magnetic field remains constant and is oriented along the strike of the formation.3 As shown by d'Erceville and Kunetz," all the information about the anomaly is contained in measurements of the electric field component. In fact, away from the interface, the electric fields are proportional to the square roots of the resistivities:

Jan 1, 1970

By E. P. Fleming

COMPARED to the situation abroad, the domestic industry continues to lag both as regards the production and consumption of newly mined lead. During 1938 we produced and consumed slightly over 20 per cent of the world output, whereas ten years ago the figure was nearly double this pro- portion. Labor difficulties and absence of demand were chiefly responsible for the general inactivity. In the foreign field, in spite of low metal prices, production and consumption of lead equaled or exceeded all previous records. Practically all the large companies, with the exception of those in Spain, increased operations, though it should be noted that the foreign lead mines have higher-grade ores than domestic mines. In view of the rapid expansion of the foreign industry, it is natural to expect greater progress abroad, particularly in process metallurgy.

Jan 1, 1939

By Arnulf Muan, Egil Aukrust

Activities of COO in the three solid solution series COO-MgO, COO-MnO, and COO-"FeO" have been determined at 1200°C by equilibrating oxide samples with a metal phase (cobalt or a Co-Fe alloy) in atmospheres of known oxygen activities. The systems COO-MgO and COO-MnO are ideal, within limits of experimental error, whereas the system COO-"FeO" shows a slight positive deviation from ideality at the temperature of this investigation. KNOWLEDGE of activities of oxide components in solid solutions is necessary for the calculation of the cation distribution among coexisting oxide phases in many important metallurgical, ceramic, and geochemical systems. Very few activity-composition curves are available for such systems at the present time. A start on the prodigious job of obtaining such data has been made by studies of solid solutions with simple sodium chloride type structure containing NiO or "FeO" as a component.1-3 The present paper describes similar studies for solid solutions with sodium chloride type structure containing COO as a component. For the systems COO-MgO and COO-MnO, the activity solid solution is determined by the equation Here po and are the oxygen activities of the gas phase in equilibrium with the phase assemblages metallic cobalt plus oxide solid solution, and metallic cobalt plus pure COO, respectively. In the system CoO-"Fe07', the metal phase is a Co-Fe alloy rather than pure cobalt. In this case the activity of COO in the oxide solid solution is calculated from the equation where a& is the activity of cobalt in the metal phase. Because the system Co-Fe is close to ideal4 and the metal phase appearing in the present work contains less iron than cobalt even at the lowest COO concentrations of the oxide phases used may be set equal to N . Hence, Eq. [2] becomes The value of Nc, can be estimated from the relative stabilities of the oxides COO (see below) and I) EXPERIMENTAL METHOD Two different but closely related procedures were used in the present investigation to determine the activity-composition curves. In one method, the oxide solid solutions were equilibrated against

Jan 1, 1963

By Donald J. Worth

INTRODUCTION Minera Real de Angeles makes a very interesting case study in more ways than one. To begin with, it represents the first time a bulk silver deposit has been put into production in Mexico. Second, the feasibility and financing stage spanned a period when the silver price ranged from $4 to $40 per ounce. Third, there was a major devaluation of the peso and a financial crisis in Mexico at completion of the project. Fourth, the composition of the partnership (a major Canadian mining company, a major Mexican mining company and the host government's own mining entity) is worthy of note. This paper gives considerable background on the project and how it came to fruition. The political risk aspects and how the major provider of funds perceived Mexican risk at the time of decision to participate and afterwards are highlighted. LOCATION AND HISTORY The Real de Angeles deposit is located at an elevation of 2300 meters in Central Mexico in the State of Zacatecas (Figure 1). The closest village is Noria de Angeles, three kilometers to the north. The closest cities are Aguascalientes, Zacatecas and San Luis Potosi. The first-mentioned is one hour to the southwest by automobile over good roads. Exploitation of the vein outcrops probably began towards the end of the sixteenth century by the Spanish. Evidence of past mining activity is shown by numerous shafts, manways, dumps and ruins. Also, there were remnants of two rudimentary concentrating mills now obliterated by pit development and in the nearby town of Noria de Angeles the ruins of a small smelter still exist. Compania Minera Gamma, an affiliate of a major international mining company, investigated Real de Angeles from 1969 to 1971. Its evaluation program included 20 drill holes and comprehensive geological engineering and metallurgical studies. The results were not encouraging and the option on the property was dropped. In late August 1973 geologists representing Placer Mexicana which was later renamed Explomin were advised of the availability of the property and liked the prospects sufficiently to make an option payment soon due and to agree to outright purchase by year-end. A series of 34 holes were drilled by Explomin and a preliminary study indicated that the prospect had mine-making potential if the silver price was right. [ ] DESCRIPTION OF THE PROJECT Real de Angeles is best described as a large, low grade open pit silver mine because at today's prices approximately 70% of the realizable revenue is derived from that metal. One must also keep in mind that the operation produces two concentrates - a lead concentrate with high silver content and

Jan 1, 1985

By John B. Hastings

TEN miles from Hartsel, near Antelope springs, in Park county, Colorado, there is a large area of unconsolidated lake beds, which are interesting because at least a part of the lacustrine sands contains in the aggregate an immense amount of gold. During 1906, one of the arms of this dessicated lake was fairly well prospected with shafts and cuts by an Eastern company to test its value, as favorable amounts of gold had in some instances been found upon it. The claims of the company contain about 5,000 acres of the beds; but this is only a small portion of them, a south branch from a main body, which is at least 7 miles in diameter, with other and very wide lateral gulches, paralleling the one herein described on the east and west. A certain amount of digging and sampling was done in the outside areas; but the result was evidently unsatisfactory, since the work was discontinued. his section of Colorado has not been studied geologically, and the age of the ancient lake is unknown. It is probably Quaternary. I spent two weeks on the ground, in September and October, 1906, but was quite absorbed in the sampling. I looked, however, for terraces on the rim-rock and other evidences of movement and erosion, but did not find anything to denote an earlier age than the Quaternary. The granite rim-rock may be Archean; S. F. Emmons says that some of the granites in central Colorado are as old as that. The rim-rock as observed is a gray quartzose biotite-granite, except a small area in Sections 3 and 34, where it is a felsitic (?) breccia. The breccia is silicified by solfataric action at the corner near Shaft No. 7, in Section 34; but this action is older than the sands and does not extend to them. The shaft averaged 50c. per ton, more than twice as much as the rest.

Jan 5, 1908

By A. J. Williams

THE province of Saskatchewan, situated in the center of the Great Plains region of Canada, has, like most prairie areas, an essentially agricultural economy. Most of its population of about 860,000 is located in the southern half of the province in the farming and ranching areas. To the north of the prairie is a broad forested belt supporting a considerable timbering industry, and the northern one third of the province is glaciated pre-Cambrian rock formation. This latter area is relatively barren of vegetation, but the presence within it of a considerable variety of radioactive, noble and base metals, and industrial minerals has been shown by prospecting in recent years.' Glacial Geology The Keewatin ice sheet, considered to have accumulated in the country to the west of Hudson Bay in Pleistocene time, covered at its maximum advancement almost all of Saskatchewan and extended south of the international boundary. Only in the Cypress Hills in the southwest and around Wood Mountain in the south central portion of the province did the preglacial formations escape the action for this glacial period. The bedrock of the plains and forest areas therefore is overlain by moraines and modified glacial drift, which vary in thickness from a few feet to 400 or 500 ft.' Glacial action in the pre-Cambrian area of the province was largely erosional, most of the more recent formations and some of the pre-Cambrian rock being transported out of the area to the south and west. It has been estimated that about 13 pct of this area is composed of lakes and rivers not too adaptable to rail or water transportation, so that until the use of aviation for exploration purposes became general, development of the area was slow. To the south, the heavy mantle of glacial drift has to some extent deterred the discovery of industrial minerals in the bedrock underlying the forest and prairie regions3 At the same time, this drift contains numerous deposits of those most elementary and necessary industrial minerals, sand and gravel. Sedimentary Basin The major feature of the sedimentary deposits underlying the plains regions is the basinal structure known as the Moose Jaw syncline, which runs from the southeast corner of the province in a northwesterly direction. To the west of this syncline the formations curve upward, then have been faulted and further upthrust to appear at the surface in the foothills of the Rockies in Alberta; to the east and north they curve upward into Manitoba and northern Saskatchewan, but the surface contacts are covered mostly with glacial drift.238 The axis of the syncline dips to the southeast, so that there is also an upward trend of the formations along the axis to the northwest. In illustration of the regional structure underlying the province, the pre-Cambrian basement has been logged in drillholes at the following depths in several locations: Ogema (south central), 9390 ft; Gronlid (northeast), 2599 ft; Vera (northwest), 4422 ft; Big River (north northwest), 2348 ft. Fig. 1 indicates the general surface geology of the province, ignoring such glacial overburden as may overlie many of the bedrock formations. Also indicated is the approximate location of the axis of the Moose Jaw syncline.' Industrial Minerals Clays: The province is fortunate in possessing a widespread distribution of clays of ceramic value, ranging from those used for heavy structural products to the high grade pottery and china clays. Shales suitable for brick and tile production are found in the Upper Cretaceous and Tertiary formations across the south of the province where the glacial drift is thin or nonexistent. Many deposits of glacial lake clays suitable for such wares are found scattered over the rest of the province south of the pre-Cambrian area. The Whitemud formation of the Upper Cretaceous is a narrow sedimentary band of secondary clays found intermittently at points across the south of the province where glacial action did not disturb or remove them.' In the southwest corner of the province, around Eastend in the Frenchman River valley, the refractory clays of this formation are contaminated somewhat with iron compounds or other alteration products of basaltic rocks. This eliminates the use of those clays in true whitewares, as they fire to creamy buff shades at the lower temperatures and to a blue-specked grey at cone 8 to 12, (2280°F to 2390°F), the range commonly used in firing whiteware. However, for use in the production of colored artware, caneware, stoneware or crockery, and sewerpipe, this type of clay makes an excellent body that requires little or no addition of flint, feldspar, or other fluxing materials such as are required in the higher class of ware.' It is not a grade of clay that can be shipped great distances to the manufacturing centers, but a market for considerable tonnages has developed at nearby Medicine Hat, where cheap natural gas is available for the firing of the ware. Farther east in the south central portion of the province, the clays of the Whitemud formation are generally more refractory and white burning. The formation is divided into three zones, consisting of white clays, brown shale, and white sandy clays.

Jan 1, 1953

By A. J. Williams

THE province of Saskatchewan, situated in the center of the Great Plains region of Canada, has, like most prairie areas, an essentially agricultural economy. Most of its population of about 860,000 is located in the southern half of the province in the farming and ranching areas. To the north of the prairie is a broad forested belt supporting a considerable timbering industry, and the northern one third of the province is glaciated pre-Cambrian rock formation. This latter area is, relatively barren of vegetation, but the presence within it of a considerable variety of radioactive, noble and base metals, and industrial minerals has been shown by prospecting in recent years.1 Glacial Geology The Keewatin ice sheet, considered to have accumulated in the country to the west of Hudson Bay in Pleistocene time, covered at its maximum advancement almost all of Saskatchewan and extended south of the international boundary. Only in the Cypress Hills in the southwest and around Wood Mountain in the south central portion of the province did the preglacial formations escape the action for this glacial period. The bedrock of the plains and forest areas therefore is overlain by moraines and modified glacial drift, which vary in thickness from a few feet to 400 or 500 ft.2 Glacial action in the pre-Cambrian area of the province was largely erosional, most of the more recent formations and some of the pre-Cambrian rock being transported out of the area to the south and west. It has been estimated that about 13 pct of this area is composed of lakes and rivers not too adaptable to rail or water transportation, so that until the use of aviation for exploration purposes became general; development of the area was slow. To the south, the heavy. mantle of glacial drift has to some extent deterred the discovery of industrial minerals in the bedrock underlying the forest and prairie regions.3 At the same time, this drift contains numerous deposits of those most elementary and necessary industrial minerals, sand and gravel. Sedimentary Basin The major feature of the sedimentary deposits underlying the plains regions is the basinal structure known as the Moose Jaw syncline, which runs from the southeast corner of the province in a northwesterly direction. To the west. of this syncline the formations curve upward, then have been faulted and further upthrust to appear at the surface in the foothills of-the Rockies in Alberta; to the east and north they curve upward into Manitoba and northern Saskatchewan, but the surface contacts are covered mostly with glacial drift.2,3 The axis of the syncline dips to thee southeast, so that there is also an upward trend of the formations along the axis to the northwest. In illustration of the regional structure underlying the province, the pre-Cambrian basement has been logged in drillholes at the following depths in several locations: Ogema (south central), 9390 ft; Gronlid (northeast), 2599 ft; Vera (northwest), 4422 ft; Big River (north northwest), 2348 ft. Fig. 1 indicates the general surface geology of the province, ignoring such glacial overburden as may overlie many of the bedrock formations. Also indicated is the approximate location of the axis of the Moose Jaw syncline.4 Industrial Minerals Clays: The province is fortunate in possessing a widespread distribution of clays of ceramic value, ranging from those used for heavy structural products to the high grade pottery and china clays. Shales suitable for brick and tile production are found in the Upper Cretaceous and Tertiary formations across the south of the province where the glacial drift is thin or nonexistent. Many deposits of glacial lake clays suitable for such wares are found scattered over the rest of the province south of the pre-Cambrian area. The Whitemud formation of the Upper Cretaceous is a narrow sedimentary, band of secondary clays found intermittently, at points, across the, south of the province where glacial action did not disturb or remove them.8 In the southwest corner of the province, around Eastend in the Frenchman River valley, the refractory clays of this formation are contaminated somewhat with iron compounds or other alteration products of basaltic rocks. This eliminates the use of those clays in true whitewares, as they fire to creamy buff shades at the lower temperatures and to a blue-specked grey at cone 8 to 12, (2280°F to. 2390°F), the range commonly used in firing whiteware. However, for use in the production of colored artware, caneware, stoneware or crockery, and sewerpipe, this type of clay makes an excellent body that requires little or no addition of flint, feldspar, or other fluxing materials such as are required in the higher class of ware.9 It is not a grade of clay that can be shipped great distances to the manufacturing centers, but a market for considerable tonnages has developed at nearby Medicine Hat, where cheap natural gas is available for the firing of the ware. Farther east in the south central portion of the province, the clays of the Whitemud formation are generally more refractory and white burning. The formation is divided into three zones, consisting of white clays, brown shale, and white sandy clays.

Jan 1, 1952

By John B. Pearse

IN order to get an idea as to the strength of steel rails, it will be well to review the tests to which iron rails have been subjected. In England, Mr. Ashcroft found that the best 80 pound rails broke under a 300 pound weight, falling 15 feet. In Germany the Society of Railway Managers determined on and have long applied a test of 1000 pounds falling 101 feet, as the standard which all first-class iron rails must reach. In this country no inspection nor test is applied, but tests made show that iron rails from our most reliable makers, break under a 6 foot fall of a 1500 pound drop as an extreme test, most of those tested breaking under a far less test; some breaking with less than a 3 foot fall of the same weight. Everywhere where steel has been used, engineers have come to the conclusion that some test is required to show the regularity and strength of the product. As compared with iron, the tests which steel will stand are wonderful. After numerous experiments partially based on the experience of the rail-mill at Graz, belonging to the Southern Railway of Austria, the Society of German Railway Managers fixed upon a test of 2000 pounds falling 13 1/2 feet. They found that this test represented the steel which suited their necessities, and also found that with steel of otherwise average purity, this test represented about one-half per cent. of carbon, and made it a rule to take no steel containing under three-tenths of a per cent, of carbon, because it was too soft. They expressed a hope that a harder steel could soon be made tough enough to stand the same test. In England, a test was adopted of 2240 pounds, falling 15 to 17 feet on the rail on heavy bearings. This test has been found satisfactory under heavy traffic on average road-beds, and has been invariably

Jan 1, 1873