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Jan 1, 1932

By F. J. Norton

THE object of this investigation was to make a comprehensive study of the degassing of molybdenum in order to determine how rigorous a treatment was necessary to completely remove sorbed gases from molybdenum electrodes in vacuum tubes. Some work has also been done with tungsten, nickel and carbon. As a logical development of this work it has been shown that the gas is present throughout the body of the metal and a study has been made of the solubility of nitrogen in molybdenum and tungsten and the rate of diffusion of nitrogen through molybdenum has been calculated. Tests were made on molybdenum from all the commercial sources and no difference was discovered in the nature of the gases present, the amounts or the ease of removal. The reason for this was apparent when a study was made of the manner in which gases are absorbed by gas-free molybdenum. It is necessary to heat molybdenum to 1760° C. in a vacuum of the order of 0.001 micron for a time which varies lineally with the thickness, in order to obtain a condition in which no further gas is evolved by the sample. A sample so degassed can be handled and subsequently assembled in a tube and then degassed readily. The gases obtained from molybdenum are carbon monoxide and nitrogen, the nitrogen being the more difficult to remove.

Jan 1, 1932

By Scott, Turner

MY whole life has been spent in the mining business, PO I naturally tend to address my remarks particularly to the newly-graduated mining and metallurgical engineers among you. To a certain extent, all forms of engineering principles are involved in the training of the mining engineer, and most sorts of engineering are certainly utilized by him, so every one of this graduatins class is concerned with the field I propose to discuss.

Jan 1, 1932

By C Gunther

Many definitions have been advanced and many limitations advocated in the use of the terms, veins, lodes and ledges. The following definitions appear to follow the best usage. A fissure vein, according to Lindgren, is a mineral mass tabular in form as a whole, though often irregular in detail, filling or accompanying a fracture or series of closely set and intimately related parallel fractures in the enclosing rock, the mineral mass having been formed later than both the country rock and the

Jan 1, 1932

Jan 1, 1932

By John Norton

THE tremendous increase in the use of metals that have been prepared by the various cold-working processes during recent years has greatly stimulated the investigation of problems concerned with the fundamental nature of these processes. It has been observed in practice that different methods of bringing about the same dimension changes in a sample result in a rather wide range of properties. Cold working reduces the ductility of a metal, or what is perhaps more nearly correct, its "working capacity," and naturally the manufacturer wishes to produce an article that has as large a working capacity as possible, and to produce it with the smallest number of operations, It has also been known for some time that cold deformation produces a parallel alignment of the crystal grains of a metal, and that the type of this preferred orientation depends to some extent at least upon particular processes employed in the deformation. The present investigation has for its purpose the study of the relations between the various factors of a cold-working process and the preferred orientation of the metal crystals resulting from this deformation. The work is chiefly confined to a study of cold-drawn seamless tubing.

Jan 1, 1932

By C. E. Lawall

WHEN this study was started very little information was available, regarding the physical characteristics of West Virginia coals. This was particularly true of friability and of crushing strengths of the coals. Some work had been done on specific gravity studies but the available information applied to only a few coals. In practically all coal-classification systems thus far proposed, the predominating factors of classifications are largely based on the chemical characteristics of the coal. Recently some investigators have pointed out that a classification based on chemical and physical properties of coal might serve to place coals in their proper group better than classification systems based on chemical properties alone. One of the aims of this study was to obtain some data on the physical properties of coal which might help to properly classify West Virginia coals.

Jan 1, 1932

By Newell G. Alford

With the workable area of coal prospected and known as to workability and quantity and sampled and tested for desired quality comes the determination of the projection and method of working. The best method will be the one supplying the greatest degree of safety, the most merchantable product, the minimum average cost per ton with the largest yield of recoverable coal. Based on coal elevations, taken at the bottom of the seam on all known outcrop exposures, prospect openings or drill holes, coal contours are made on the map to be used in developing the mining plan. The contour interval should be as close as available information will permit. For general utility in layout of mining, haulage, drainage and ventilation, a map scale of 400 ft. per in. is preferable. In mountainous sections, location of the main out- crop opening or hoisting shaft is often limited by the available railroad route and amount of land level enough for a plant site. In level country, where a tipple and hoisting shaft may be placed at will, choice of the plant site should depend on the minimum average underground haul for the total coal to be worked to the new

Jan 1, 1932

By R. E. Tremoureux

This paper describing the methods and costs of quarrying limestone at Sloan, Nev., is one of a series of similar papers being prepared for and published by the Bureau of Mines on this industry in the United States. These papers are designed to disseminate information regarding the methods used. The cost tabulations represent local operating expenditures only and not total production costs. It is recognized that publication of total production costs might in many instances cause embarrassment to individual producers as well as to the industry as a whole. On the other hand, operating costs are essential to the technical discussion and study of the methods Employed. The attention of the reader is specifically called to this differentiation in order that no misunderstanding of the scope of the cost tabulations shall ensue. The quarrying operations at Sloan are interesting not only from a technical viewpoint and because of the magnitude of the deposit, but also because the quarry is located in a desert region far removed from the centers of population where lime is used. The quarry and plant are in Clark County, Nev., 20 miles west of Las Vegas, which is the nearest town to the site of the Boulder Canyon Dam. Sloan is on the main line of the Union Pacific Railroad connecting Salt Lke City and Los Angeles. The latter city is 280 miles from Sloan and it is the shipping, point for all supplies.

Jan 1, 1932

By Evans A. F

Arising out of the increasing demands for efficiency in modern ore-dressing operations has grown a requirement for fuller knowledge of the characteristics of the ore treated. In part, this is being met by improved methods of study of the mode of occurrence of the constituent minerals, and of the intricacies of their physical relationships.A typical instance of the need for such a study is the presence of some undesired mineral in a flotation concentrate or tailing, which may be due either to mechanical association through insufficient grinding, or to incomplete separation in the flotation operation.Again, with modern practice in fine grinding, which often requires that from 70% upwards of the ground ore shall pass a 200-mesh screen, it is obviously impossible to obtain data on comparative grinding efficiencies, for instance, unless there is adequate knowledge of the size-composition of the material passing the finest available screen.Studies like these can be made satisfactorily only after size-separation (which may be carried out conveniently by elutriation) and by actual visual examination with the aid of a microscope, and the minute size of the mineral grains to be examined has necessitated the development of a new technique of sizing and microscopic examination.

Jan 1, 1932

By Albert J. McIntosh

In discussing the petroleum products situation the first thing that comes to mind is "what is happening to gasoline." Is the consumption increasing? How is the export market? What about imports? Are stocks on hand too high? Have we produced too much? This paper will attempt to answer these questions. Consumption of gasoline (motor fuel) in the United States in spite of the depression and the chaotic conditions of many industries has increased during 1931 about 2 per cent over 1930. This favorable factor was offset by a severe contraction in exports, which fell off about 30 per cent from 1930. This drop in exports was so large that very little more export business was done than in 1926 or 1927. Taking all demand combined, there was a decrease from the peak year of 1930 of nearly 11,000,000 bbl., amounting to slightly over 2 per cent. The units of the industry, though, should have expected some decrease and governed themselves accordingly. Let us see what they did. They reduced imports over 3,000,000 bbl., which helped. Production was cut 3,000,000 bbl., but this was not enough, so that stocks increased 1,800,000 bbl. whereas during the previous year stocks were reduced 2,500,000 bbl. It is apparent, therefore, that something was done to keep the industry in balance in regard to gasoline, but not enough. If the year had ended on Sept. 30, we could have said that production had been cut 19,000,000 bbl. and stocks had been reduced from the previous year, but the excessive production during the last three months of the year changed everything. It is a strange thing and worthy of note that the price of gasoline fell to its lowest levels when apparently the greatest improvement was being made, and that during the last quarter of the year prices started to improve, when, in spite of an improvement in total demand which approximated 1930, an excessive production caused an uneconomic condition to set in. Stocks on hand on Dec. 31 were unquestionably too high, possibly 10,000,000 bbl. more than was needed for a strong condition to obtain. It seems almost unbelievable that the industry would continue to produce

Jan 1, 1932

By Howard S. Bryant

The state of Kansas in 1931 continued to hold fourth place on the list of oil-producing states, despite the fact that low prices for crude oil curtailed drilling to just one-half the amount done in 1930, which itself was the lowest in the preceding 10 years. The estimated crude oil production for 1931, according to sources available to the writer, will approximate 37,037,000 bbl., the lowest since 1925. Thus Kansas produced one-eighth less oil this year than it did last year when it produced 42,729,085 barrels. This year's development was characterized by a very small amount of wildcat drilling; however, large new areas were semiproven for oil production, and several thousands of acres were added to the actually proved areas in western Kansas, so that the state now has larger proven areas of oil reserves than at any time in its history since the heyday of the famous El Dorado pool. The general prospects for oil production in the near future are indeed promising for central western Kansas, where drilling costs are moderate and depths are relatively shallow compared to the remaining unexplored parts of the northern Mid-Continent area. Probably the greatest singular achievement in the state for 1931 was the development of its natural gas reserves. This development took place principally in two spots, McPherson County in central Kansas, and Stevens and Morton counties in southwestern Kansas, and it is a matter of record that more than one and one-half billion cubic feet of open-flow capacity per day were added to reserves, nearly twice the amount developed in 1930, previously the largest amount in the history of gas development in Kansas. Gas pipe lines already built and now building are in position to deliver natural gas by one system to Chicago, Ill., by another to Indianapolis, Ind., from whence lines already lead practically to the Atlantic seaboard, and to other cities large and small located west, northwest, north and northeast of Kansas. Table 2 shows all well completions for 1931 in a form to compare with the results of previous years.

Jan 1, 1932

By H. Shaw

In the author's previous paper an attempt was made to analyze in detail the gravitational effects arising from certain subterranean anomalies of simple form, and extending to infinity in three directions. As a result of this critical examination, certain features—which were considered to be characteristic of the anomalies under investigation—were disclosed, a close observance of which enables a complete interpretation to be reached. The most simple case was first considered; viz., that of a heavy horizontal plate, bounded above and below by horizontal planes, and extending to infinity on one side of a vertical plane containing the y axis, in the three directions + y, —y, and +x. After this, the investigation was extended to the case of a similar infinite horizontal block having an inclined face. In each case the form and behavior of the gradient curve and the curve of differential curvature were analyzed, and entirely distinct interpretations were put forward, based upon (1) the gradient, (2) the differential curvature and (3) a comparison of these two quantities. In continuation of the previous work, and as a preliminary to further analysis of more complex structures, certain factors will now be examined which characterize (1) the simple infinite vertical block and (2) an infinite block which is inclined to the vertical, formations which are of considerable practical interest, being typical of important. geological structures—intru-sive dikes, lodes, veins, etc.—and because, even though in nature these may be irregular, valuable guides to a more complete interpretation are obtained by assuming, as a first approximation, that they have the simple characteristics to be studied hereafter. In the previous paper certain preliminary assumptions were made in order to render the resulting deductions universally applicable and entirely independent of the particular scale employed. Consideration was limited to homogeneous deposits of unit positive effective density (and this condition is retained in the present investigation), so that in the case of

Jan 1, 1932

Jan 1, 1932

By B. B. Cox

Iraq, formerly called Mesopotamia in Asiatic Turkey, became a kingdom under British Mandate after the world war and is expected to gain its independence in 1932 when it enters the League of Nations. The kingdom is shown on Fig. 1 in its relations to neighboring countries, to the Mediterranean Sea and to the Persian Gulf. It is slightly smaller than the State of Texas with its capitol, Baghdad, inland about as far from the Persian Gulf as Breckinridge, Tex., is from the Houston Shipping Channel. The oil fields lie 180 to 225 miles north of Baghdad, or about as far as from Breckinridge to Oklahoma City, and about as far from the Mediterranean as Fort Worth is from Hobbs, N. M. A narrow-gage railway runs from Basra, the Persian Gulf port, to Baghdad. From there another narrow-gage runs into the Kurdish hills east of the Tigris to Kirkuk. A standard-gage, part of the old Berlin-Baghdad system, follows the west bank of the Tigris northward from Baghdad to Baiji, a village about 100 miles south of Mosul. No railway exists between Iraq and the Mediterranean, though the Anatolian Railways in southern Turkey come to within 50 miles of the Iraq frontier and 120 miles of Mosul. Surveys have been completed for a railway through British Mandates from Haifa to Baghdad as well as for a railway through French Mandated Syria from Tripoli to Abu Kemal near the Iraq border. Wagon roads, excepting those constructed by the oil companies, are few and indifferent in Iraq and no road exists across the desert to the Mediterranean, but contrary to prevalent beliefs the surface is firm and free from sand dunes so that motor cars can go almost anywhere in dry weather, with ease. Frequent motor car and airplane service exists between Baghdad and the Mediterranean ports and motor car service may be had between Kirkuk and Nisibin, Turkey, where on two days each week through Wagons Lits service is available to Paris. Baghdad is about 21 days distant from New York City with present transport facilities. The climate is semiarid, similar to Imperial Valley, California, the average rainfall outside the mountainous parts amounting generally to

Jan 1, 1932

By Oliver A. Dibble

This paper it one of a series being prepared for and published by the United States Bureau of Mines, describing mining methods and costs at clay pits throughout the United States. These papers are designed to disseminate technical information regarding the methods used. The cost tabulations represent operating expenditures only and not total costs. It is recognized that publication of total costs might in many instances cause embarrassment to individual operators as well as to the industry as a whole. On the other hand, operating costs are essential to the technical discussion and study of the methods employed. The attention of the reader is specifically called to this differentiation in order that no misunderstanding of the scope of the cost tabulations shall ensue. The open-pit recovery of clay for cement plants is a comparatively simple operation in comparison with underground mining of clays; nevertheless, it represents an appreciable factor in the cost of cement manufacture. The following report deals specifically with the methods employed by the Aetna Portland Cement Co., which operates cement mills at Fenton and Bay City, Mich., in recovering clay from their pit at Corunna, Mich., on the Grand Trunk Western Railway.

Jan 1, 1932

By E. B. Swanson

There is only one way to transport natural gas and that is by pipe lines. In the past few years, these lines have been extended rapidly into areas which previously had been served mainly by solid and liquid fuels. In the subject given me, this extension is referred to as an invasion, which implies a rather forceful entry. Whether or not such an implication may be applied to recent natural-gas developments is unimportant. It is the fact of the extension, not its definition, which is important. For centuries, natural gas has been utilized for various purposes in many parts of the world. It was the foundation of fire worship at Baku. The Chinese used it for the evaporation of brine in salt manufacture. In our country, its history seemingly dates back 110 years to the vicinity of Fredonia, N. Y., where seepage gas was assembled and used for lighting purposes. A few years later, a %inch pipe was laid to a lighthouse on Lake Erie, and the early records of the Lighthouse Service tell of the difficulties surrounding this use. With the discovery of oil in Pennsylvania, there followed further development; the town of Titusville was piped with natural gas and, some few years later, gas was made available for manufacturing plants adjacent to the oil fields. For more than a half century, the industry was concentrated in the

Jan 1, 1932

By C. K. Leith

1 apologize for attempting to talk in a field in which 1 am by no means a specialist, but some of the problems brought up have much in common with other minerals. It touches the field in which we are all interested and it is a field in which our Mineral Inquiry has been giving special attention during the last two years. While it is the primary business, of course, of this Institute to consider the physical facts and technology of minerals, we now face the necessity of considering the minerd industry in its broader economic, social, and political relationships. We have run into a traffic jam—as though a load of hay had been spilled on the road. It makes no difference whether we are drivers or passengers, technical or nontechnical men, we have to get the load off the road before we can go farther. We are conscious of very many difficulties which are outside of the ordinary range of cost accounting or methods of mining or the usual thing with which we concern ourselves. We have extensive readjustments to make in our social and economic and political contacts. It is up to us to find out what is the matter. As a matter of fact, we do not know what is the matter in any comprehensive way. We have many suggestions as to difficulties here and there. Many people are working on the problem, but when the mineral industry as a whole is asked what is a reasonable course of procedure, what is its program, what would be a reasonable state or national policy, I think you will agree with me that we have no spokesman able to outline even a semblance of such a general policy. We sit back and criticize when somebody else steps in, as Governor Murray stepped in, and as many others of our state governors and legislators are stepping in, to do things which we do not think are reasonable. When they say, "What is a reasonable program? " we find ourselves caught napping. We have not agreed on a program. The other day in talking with one of the leaders of the western radical movement, I was twitting him on having no sound and comprehensive conservation program. He said, "What is yours, and what is the program of the mineral

Jan 1, 1932

By Edgar Stansfield

ONE of the most striking features of the coal series passing from peat through brown coal, lignite, etc., up to anthracite is the gradual reduction of moisture content with the increased coalification of the original plant material. Thus drained peat from a bog may contain 90 per cent water, brown coal contain 50 per cent, lignite 30 per cent, while a bituminous coal may contain only 1 per cent moisture. Moisture, therefore, is one of the important factors to be considered in coal classification, especially with the lower rank coals. With bituminous and higher rank coals the moisture content is less satisfactory for classification; it may even pass a minimum value and then increase with increasing rank to anthracite and superanthracite. Coal in an undisturbed seam contains moisture which is an integral part of the coal, but it may also be wet with free, underground water percolating through the seam. Only the former must be considered in evaluating the moisture content of the coal for classification purposes; this will be called the "true moisture" of the coal. When the seam is mined and sampled the sample taken may show the true moisture; on the contrary, it may contain in addition free mine water or, especially in dry, well ventilated mines, it may contain less than the true moisture. Coal contains unstable organic compounds which may decompose, with the production of moisture, when the coal is exposed to air at ordinary temperatures, or is heated with or without exposure to air. The potential moisture of a coal therefore is higher than its actual moisture. The lower the rank of the coal, the greater its instability, as a rule, and the greater the care necessary to avoid oxidation or decomposition in any investigation of moisture content. The majority of coal workers have preferred, on account of the difficulty in evaluating the true moisture of a coal, and for other reasons, to classify coals by analyses calculated to the dry-coal basis. A number of workers familiar with lower rank coals have recently insisted that the classification of such coals can be satisfactory only if analyses on the moist-coal basis are employed. The moisture-holding capacity of coal is therefore intimately connected with coal classification, and in this paper a procedure is outlined for determining the true moisture of a coal.

Jan 1, 1932

Jan 1, 1932