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By M. Amsterdam, F. Rothwarf, L. Muldawer

SILVER-cadmium near the composition AgCd shows three equilibrium phases. As with 13 brass, the high temperature phase is disordered body-centered cubic (8) and the low temperature phase has the ordered CsCl structure . However, there is an intermediate temperature phase which is hexagonal close-packed ((). In a recent paper, Speich and Mack' report on a study of the Ag-Cd eutectoid near the AgCd composition. Unfortunately, the phase diagram upon which they base some of their conclusions is incorrect. That diagram is taken from the Metals Handbook' and the error is that the 0 and ( phases have been interchanged. The Handbook gives the low temperature phase as hexagonal (designated 5) and the intermediate temperature phase as cubic ordered (designated . The error may be typographical or it may be one of confusion resulting from the use of 5, ,, and 0 for the intermediate phase in various papers. A careful search of the literature reveals that a number of authors have indicated the correct relative positions of the 13, 5, and 0 phases. The comprehensive work of Fraenkel and Wolf clearly stated that the high and the low temperature phases are either identical or are very similar. olander,' on the basis of electrochemical measurements, showed that the 13 phase is disordered and the 1 phase (designated 8" in his paper and in refs. 3 and 5) is ordered. Further work by Durrant5 using thermal and metallographic analyses provided a more precise phase diagram. A summary of these works was given by Hansen6 and shows the correct relative positions of the phases. Owen, Rogers, and Guthrie7 located correctly the upper two phases by X-ray diffraction. Their failure to find the low tem-

Jan 1, 1954

Early production records are practically nonexistent, although the early geological survey reports mention a number of mines as being in operation at the dates of the field surveys. Reports of the Bureau of Statistics began in 1878, and as usual, the tonnages reported were undoubtedly small. County histories gave some production figures, but not many. The use of the Indiana block coal in blast furnaces furnished a substantial market for a number of years, which ended about the close of the Civil War. Some coke was made from Indiana coal for several years in the eighteen-forties, as is described in the chapter on Coke. (Chapter 35.)

Jan 1, 1942

By W. N. Logan, P. Simpson

There was less activity in the petroleum industry in Indiana in 1933 than in previous years, owing largely to adverse market conditions. The only development of any consequence was for oil in Perry and Vander-burgh counties in southwestern Indiana, a few gas wells being brought in in Jay County in northeastern Indiana. Indications are that there will be more activity in southwestern Indiana in 1934. Little change may be expected in northeastern Indiana. One hundred and sixty wells were drilled in Indiana in 1933, of which 57 were dry, 44 produced oil, 38 produced gas and 21 either were not completed or information on them was lacking. There were 153 wells abandoned and plugged in 1933, as compared to 205 in 1932. Southwestern Indiana This area centers about Gibson County and is the principal source of oil and gas production in the state. Production is from the Lower Pennsylvanian and Upper Mississippian formations. Oil production for 1932 was approximately 847,000 bbl. and for 1933 was 804,000 bbl. Gas production for 1933 was 942,000,000 cubic feet. The Siosi field, in southwestern Vigo County and northwestern Sullivan County, discovered six years ago, produced approximately 244,000 bbl. in 1932 and 223,000 bbl. in 1933. Production is from Devonian and Silurian formations. The oil is high gravity, but contains considerable sulfur. The Shelburn and other small pools in central Sullivan County produced approximately 68,000 bbl. in 1932 and 2,000 bbl. less in 1933. Production is from one or more of five horizons in the Pottsville and is obtained at 600 to 800 ft. This area also produces approximately 19,000,000 cu. ft. of gas a year, supplying the city of Sullivan. The field is over 20 years old. The Gibson-Pike County area, made up of many small pools, including several in southern Knox and southwestern Daviess counties, produced approximately 486,000 bbl. in 1932 and 450,000 bbl. in 1933. This production is from the Mansfield sandstone of Pennsylvanian and/or

Jan 1, 1934

By A. W. Edelen, H. V. Lee

THE Teziutlan copper-zinc deposit is supposed to be of late Cambrian or early Paleozoic age. The country rocks are a series of schists or phyllites, flat lying and in the form of a plunging anticline. The ore deposit occupies a single horizon in the schist for a known horizontal extent of 1200 meters. Along its strike occur four large lenses or ore bodies. These ore bodies occupy positions along the flank and extend to the crest of the anticline. The primary mineralization is in the form of quartz, pyrite, sphalerite, chalcopyrite and galena, with a few scattered silver anti-monides. Quartz and pyrite form the mineralization between the ore lenses. In the ore lenses the sulphides appear as a massive, very he-grained intergrowth of minerals. The intergrowth suggests a contemporaneous deposition of the heavy sulphides. The grain size, usually under 0.09 mm., makes the separation difficult and fine grinding important. The ore bodies were formed at great depth by solutions probably originating in the same basic magma that gave rise to the dolerite sills that are so common in their vicinity. INTRODUCTION The Teziutlan copper-zinc deposit is distinctly different from other ore deposits of Mexico in age and type. Previously stated to be pre- Cambrian in age, it is now quite generally supposed to belong to the late Cambrian or to the early Paleozoic period. Also, in contrast to the usual shallow-vein zone type of mineralization in Mexico, there is here exemplified an intermediate vein zone deposit of copper and zinc. So far as is known, the Teziutlan vein is unique in the history of Mexican geology and in a class by itself, its closest counterpart probably being the copper veins of the pre-Cambrian of Canada. The Teziutlan district is in the extreme northwestern corner of the State of Puebla, Mexico. Teziutlan, the terminus of a branch line of the National Railways from Mexico City, is connected to the mine at Aire Libre by a 17-km. narrow-gauge railroad owned and operated by the Teziutlan Copper Co. Owing to excessive grades on this short line, Shay-geared locomotives are used for the transportation of concentrates and supplies.

Jan 1, 1937

By James M. Schopf

Gilbert H. Cady (Senior Geologist, Head of Coal Division Emeritus, Illinois State Geological Survey, Ur-bans)— Those coal mining and preparation engineers and operators who read this article will probably be most concerned with those parts which deal with the applied aspects of coal petrology in the fields of mining and technology. Actually the two categories overlap to such a degree that they are essentially one. The article appears to suggest that there are two points of veiw in the field of applied coal petrology. From one viewpoint the interest is in the attributes of the various macerals (Fig. 4)—vitrinite, exinite, and inertinite—-in terms of utilization (when the coal is burned, coked, gasified, hydrogenated, etc.). From the other point of view, assuming that the macerals do possess individuality in behavior, interest attaches to the possibility that coal of a particular type (maceral composition) can be prepared by discriminating methods of preparation and blending. Most of the 29 items listed for mining and technology can be assigned to one or the other of these two categories. Somewhat the same simplicity that resides in the items of the proximate chemical analysis is desirable for the petrologic analysis. This simplicity appears to be fairly well achieved by the group maceral device provided mineral matter is also included. At present, without fully adequate experimental substantiation, the three types of material represented by the group macerals vitrinite, exinite, and inertinite are regarded as sufficiently different in composition and properties so that the preponderance of any one type gives the coal distinctive properties provided it is not too high in rank. This appears to be increasingly true with coals of decreasing rank from medium volatile bituminous coals downward. The article reflects the great emphasis placed on the technique of descriptive coal petrology in America. Such description has resulted in a good understanding of the nature of the fundamental variability in the physical composition of bituminous coals. Such understanding has been attained very largely by the thin section technique used in coal bed profile analysis introduced by R. Thiessen after the manner suggested by the data assembled in Table 11. In contrast, the group maceral concept of coal analysis in terms of the categories indicated on the left hand side of Fig. 4 is particularly useful for broken coal analysis and applied coal petrology, in which evaluation is largely based on quantitative concepts. It is inadequately emphasized in this article that although the Thiessen procedure is suitable for the purpose of petrologic description in which texture and orientation are of critical importance, it is less well adapted to the technological uses of applied coal petrology. No doubt those persons whose interest may have been aroused in the possibilities of more refined coal preparation by this and other recent contributions to the literature of coal petrology will understand that certain technical aspects of coal petrology, particularly in the field of descriptive petrology, are still a matter of some controversy among the coal petrologists, but they will also appreciate that Schopf has made an important contribution to the field of coal petrology in America by pointing out that such petrology requires consideration of disoriented or broken coal samples and that results are expressed less in descriptive terms than in quantitative values with respect to the four types of material composing coal—-vitrinite, exinite, inertinite, and mineral matter. Unfortunately because so much American coal petrology has been descriptive of the coal in the bed there is a dearth of literature on applied coal petrology. Research and experimental data in this field are greatly needed.

Jan 1, 1959

By Thomas T. Read

MINING, which is at least twenty centuries old, was at first, and long, wholly a practical art. Little more than two centuries have elapsed since the inception of the idea that general education and a knowledge of natural science would be of advantage to those engaged in the mining industry. Though schools of mining began to develop in Europe early in the eighteenth century the concept of educational preparation for technical conduct of the industry was slow in winning general acceptance in the industry itself. John Hays Hammond, in his autobiography,1 recalls that when he sought employment with a mining company after he had graduated from Yale and Freiberg he had to assure its executive, before being even considered for employment, that he did not consider that he had learned anything about mining. This was as late as 1880. Existence in the industry of a prejudice against education of the academic type is perhaps an explanation why inadequate provision has been made by the mining industry for the continuing education of technical employees after they enter employment, although engineering education prior to engaging in industry has now won general acceptance. I am familiar with the existence of "loop" courses for engineering graduates in metallurgical plants, of schemes for giving mining graduates "practical experience," and of the interest in vocational courses for workmen which sprang up in the period of labor shortage during and immediately following World War I (but which quickly died when the depression of 1921 again made experienced workmen available in sufficient supply), having been chairman of a committee appointed by the Mineral Industry Education Division to make a survey of existing provisions for post-employment training for engineers in our industry. The results of that survey, reported elsewhere, clearly indicate that it is inadequate as to amount; the aim of this paper is to present evidence for belief that it is also inadequate in quality. To avoid becoming too involved, no reference will be made here to post-employment vocational training for workmen, which is a subject differing so much from post-employment education for engineers as to require separate treatment. Neither will postgraduate education for metallurgical engineers be discussed, because a distinction must then be made between training for research work and for plant operation, whereas mining engineers engage almost exclusively in operations. Since the situation in the coal-mining industry has been discussed at several recent meetings, that also will be passed over, and what follows should be taken as a discussion applying exclusively to the metal-mining industry. PROFESSIONAL DEVELOPMENT In the operations field (both in mining and metallurgy) the work to which a beginner is assigned is seldom closely related to previous academic education. The contrast is almost as great as between

Jan 1, 1941

By Carter S. Cole

Mr. Chairman, Fellow Members and Guests, our chairman this morning got over into the geneological field, so perhaps I may be pardoned if I revert to some of my ancestral training and give you a text. I always like to talk about some special little text that may illustrate what we want to say. So the text that I will take for this afternoon is a very simple one, "Win the War." That is the guide for all of our actions, or should be. We should question everything we do to see what it does to contribute to winning the war. If we fail to do that, nothing else is going to count. On the wall of the office of one of the branch chiefs in the Copper Division in Washington there is a little slogan which I think we should take very deeply to heart, "The difficult we do right away. The impossible takes a little longer." I think that is a very good guide for us to follow in the work that lies ahead of us in the metallurgical field and in the handling of these secondary metals and the things that result therefrom. My subject is "Conservation and Specifications." Some people would wonder just where that fits in, and how you might define "conservation." One very good definition would be "the utmost use of our resources." If you will pardon my going back to some of my earlier experience for a little simile, those of you who know me know that for ten years after the last war I was in the railroad business. If we are with the engineman in a cab, and we have a green signal ahead of us, that is a clear signal and tells us to proceed at full authorized speed. Now suppose we come to a yellow signal that is caution, slow down to one-half authorized speed and be prepared to stop. Now if you do slow down, the chances are that that obstruction that was ahead of you will move out of the road, and you may get another yellow or caution signal at the next block, and be able to keep going at a slow speed. As of the date of Pearl Harbor our tin supply took on a very yellow tinge, and it threw the caution sign right in our faces. If we had not heeded that sign, and cut down our consumption of tin, we would not have any today; but because we have done so we are in a much better position today than we were a year ago, that is comparing our visible supply with our present rate of consumption as contrasted with the visible supply a year ago and our then rate of consumption.

Jan 1, 1943

By David B. Reger

Widespread wildcatting for new supplies of natural gas and the beginning of importation from the southwest characterized the petroleum industry of West Virginia during 1944. Within the state, drilling for oil did not increase but. more gas wells were completed than in any previous year since 1937. Out of 40 wildcats drilled there were 25 gas discoveries and 15 dry holes. No commercial oil was found in the 40 wells. The proved limits of several oil pools were slightly extended by marginal drilling, resulting in 1300 acres of new oil territory, although no distinctly new pools were found. At least four new gas pools were assuredly discovered and various successful wildcats indicate future pools or wide extensions. The new proved gas territory, in definite new pools and definite extensions, is about 34,000 acres. A considerable net decline of proved oil has occarred and probably a slight decline of proved gas reserves. The account of operations, as gathered from trade journals and other reporting services, shows that 918 new wells were drilled, resulting in 71 oil wells with 613 bbl. of daily new production; 577 gas wells with 305,372,000 cu. ft. of daily open flow, and 142 dry holes. Also, 107 old wells were drilled to deeper sands, with 22 bbl. and 12,327,000 cu. ft. of added production. On the new wells the oil average was 8.6 bbl. per well per day, and the gas average was 529,241 CU. ft. per well per day. On new wells the ratio of dry holes to completions was 15.47 per cent. On deeper drilling the ratio of failures was 19.63 per cent. Production of oil for the year was estimated by the Oil Weekly as 3,069,000 bbl., as compared with 3,349,000 bbl. in 1943. Production of natural gas for the year is estimated by the author as 200,000, 000,000 cu. ft., as compared with the U. S. Bureau of Mines final figures of 223,789,000,000 cu. ft.t in 1943.

Jan 1, 1945

By R. Agarwal, S. Boshkov, M. T. Wane

The majority of the work done in the field of rock mechanics uses as a basis for analysis the classical linear theory of elasticity. Most workers in rock mechanics realize that removing the assumptions of homogeneity and isotropicity will bring the analysis of stress-strain relationships for geologic materials closer to reality. However, the algebra involved in reducing these restrictions is usually heavy. It is the purpose of this paper to relax the condition of isotropicity to that of orthotropicity and examine the sensitivity of this change for some simple geometries. In addition some necessary relationships between stress and strain for orthotropic materials will be developed. The recent years have seen an increasing interest in the field of rock mechanics. This is amply demonstrated by the number of articles appearing in the technical literature. The majority of these articles use as a basis for analysis the classical linear theory of elasticity. In addition, the assumptions that the material under consideration is elastically homogeneous and isotropic reduce the number of constants necessary to write an analytical relationship between stress and strain to two, e.g., Young's modulus and Poisson's ratio. Most workers in the area of rock mechanics realize that removing the conditions of homogeneity and isotropicity will bring the analysis of stress-strain relationship for geologic materials closer to reality. However, the algebra involved in analysis without imposing these restrictions is usually heavy. It is the purpose of this paper to relax the condition of isotropicity to that of orthotropicity and examine the sensitivity of this change on stress concentration for some simple geometries. In addition, it is shown that the expression for maximum stress concentration for some simple geometries considered can be further simplified if further assumptions are made. The maximum stress concentration, under these additional simplifying assumptions, is shown graphical1y. In the linear theory of elasticity, generalized Hooke's law assumes the following form

Jan 1, 1965

By E. J. Bruderlin

A metallurgical process to be economically successful must be carried on under proper conditions of control and equipment. The question of equipment is always of primary importance. In the distillation process for the recovery of zinc by retorting, the retort is the all-important piece of equipment. Each retort in a working blóck must function as a separate unit. Over-all block efficiency is the result of the ability of the individual retort to withstand the severe conditions of operation for a maximum period of time. Therefore retort manufacture has been an ever present problem with the operator of a zinc-retorting plant. During recent years the zinc-plant operator has been faced with rapid changes in the character of the ores and concentrates. Operating costs have increased as a result of the introduction of the flotation process and the amount of flotation concentrates to be handled. To counteract increasing costs, the operator has found it necessary continually to attempt heavier loading of retorts, until a 45 to 50-lb. charge per cubic foot of retort space has become common practice. Heavy loading has brought about severe firing conditions, which, in turn, have emphasized the necessity for further improving the quality of the retort. Increasing percentages of detrimental impurities in the retort charges have also added to the operator's difficulties. Amarillo Silicon Carbide Retorts At the Amarillo plant of the American Smelting and Refining Co. a retort made of a suitable plastic clay grogged with silicon carbide has been found to best meet the present-day requirements. Retorts of this kind have been in use at Amarillo for 8 years and have shown an average furnace life of approximately 175 calendar days. The Amarillo retort is cylindrical in shape and after burning is approximately 83/4 in, inside diameter by 60 in. over-all length. The wall thickness is 136 in., except for the butt of the retort, which is approximately 2½ in. thick. The retort mud has a shrinkage of 3 per cent, or approximately % in. per foot. The silicon carbide retort after being properly dried weighs about 211 lb. When the retort is fired and ready to go into use the weight decreases to approximately 203 lb.

Jan 1, 1937

By M. O. Holowaty, C. M. Squarcy

Blast furnaces are the tools of men, and it is men who have made them great. Here is presented the story of the Ironmakers-the men who first poured hot metal into what would someday be the sinews of a nation. W HEN the Jacobean merchant adventurers bade farewell to the first ship of colonists sailing for the new land, they instructed them to direct all their skill and energy to grow silk worms in Virginia. The adventurers felt sure that they could flood the market with highly priced and much desired goods like silk, sugar, tea, and indigo. They were also convinced that they would fill the needs of the mother country for iron. Early iron production in the colonies The merchants certainly had a wonderful imagination, for silk and indigo were just as exotic in Virginia as they were in England. The settlers found it more profitable to raise tobacco on the vast stretches of the free, fertile land. Thus the plans of settlers clashed with those of The Virginia Co.; and only point of agreement was the desire to produce iron. But, even there the motives of the settlers and those of The Virginia Co. of London were worlds apart. The settlers wanted to produce the tools badly needed in the colony, while the Company desired to cash in on the rising demand for iron which the home industry could not satisfy. Both the settlers and the Company lost no time trying to find iron ore. Locations of the early mines are not known. If, however, the reports of the Irishman, Francis Maguel, can be trusted, as early as 1609 a ship sailed for England with a load of 17 tons of crude iron which the East India Co. purchased at £ 4 per ton. The iron was of excellent quality and considered the best iron made of non-English ore that was ever purchased.

Jan 1, 1961

New zinc fuming plant of the Cia. Metalurgica Del Norte S.A., a subsidiary of the American Smelting & Refining Co., nears completion at the Avalos Smelter, near Chihuahua City, State of Chihuahua, Mexico. The plant is scheduled for completion on July l, 1952. The erection contractor is Utah Construction Co. Supervising engineer for Asarco is Leslie E. Harris, AIME. [ ]

Jan 1, 1952

By James R. Stuart

AS the available remaining properties of iron ore reserves on the Mesabi Range are opened up for mining, the various properties located under lake beds are brought nearer an active status. The actual physical problems involved in stripping these properties do not act as a deterrent so much as the legal and political problems that are encountered. When it is proposed to destroy a natural lake that has been used by the public for many years, much local as well as state opposition may be encountered regarding its destruction. Public hearings must be held and some adverse publicity is likely to result. The ownership of the ore under the lake and the rights of the abutting property owners must be settled, and protection from damage caused by a disturbance in surface and subsurface drainage is likely to be demanded by property owners some distance from the proposed mine area. The Embarrass Mine, located near Biwabik, Minn., falls into this classification. A portion of the orebody lies under what was formerly Syracuse Lake, this body of water having been removed in the process of stripping the mine. An additional problem in the case of a meandered body of water is the establishment of a meander line that can be projected downward as mining progresses to form the basis for a satisfactory division between lake bed and upland ore shipments for royalty purposes. Fig. 1 illustrates the complications encountered in maintaining these divisions. A balance point was agreed upon in the center of the lake to make an equable division of lake bed ore to the abutting properties. The entire lake bed has since been adjudged the property of Minnesota. Lake Characteristics Lake bed stripping problems with which this paper is concerned necessarily are limited to a specific type of lake, namely the glacial lakes of the Lake Superior region. One characteristic common to these bodies of water is a deposit of fine black mud or silt on the bottom, frequently underlain by a layer of impervious blue clay. This is also true of the muskeg areas of the region, which present almost identical problems as lakes in stripping. The actual removal of the water and the lake bed material is a routine matter more or less standardized as to equipment, and the period of time required can be estimated easily on the basis of volume and capacity. More important than the foregoing is the execution of preliminary work, and above all, the timing involved. An account could be prepared based entirely on statistical and cost data which would give a very fair picture of the time required and cash outlay needed to effect the removal of a body of water preliminary to stripping the orebody. However, the real interest from the standpoint of the operator and the engineer who carry responsibility for completion of the job lies in the unexpected emergencies and the action of various materials involved in the stripping when the balance has been upset through diversion of water courses and the reduction of the lake level. Runoff and Drainage Lakes are located in natural basins that catch all the rain water and runoff water for a considerable area. Where a lake is involved having an inlet and outlet or a sizeable water course running through it, the drainage area may include a watershed covering many square miles. All available data then must be collected to supply a history extending over as many years for which information can be gathered on the flow of streams, annual rain and snowfall, and most important, the peak flows to be expected. Where the diversion of a stream around the stripping area is a part of the problem, this last factor is of great importance since it controls the cross-section to be selected for the diversion channel and the volume to be removed in its excavation, as well as affecting the hydraulic considerations to be met in the design of the completed channel. Characteristic material in the overburden found at the Embarrass Mine is illustrated in Fig. 2. Well Pumping Pumping from the well holes was started well in advance of the draining of the lake. Fig. 3 shows a gradual lowering of the water table with no noticeable fluctuations during the period in which the lake was being dewatered. Unfortunately, because of tight ground, a maximum flow to the wells was not maintained. This retarded the rate at which the water table was reduced so that in the course of stripping the excavation soon extended below the water table, and the great bulk of the pumping was handled from a system of sumps in the pit itself. Any dewatering program projected by prepumping from wells, a glorified well point system, would have to be started well in advance of the stripping to be of any great advantage. Preliminary drainage of the surface over the mine area is entirely apart from the actual elimination of the lake bed itself. Since the lake is what is called a perched water table because of the impervious character of the lake bottom, the adjoining surface may be dewatered below the surface of the existing lake and the flow will not be affected by the proximity of that body of water. This condition actually has been demonstrated through the establishment of a number of observation holes where a small churn drill was used to put down the holes and a 3-in. pipe was installed for taking water level

Jan 1, 1952

WILLIAM H. KOBBÉ (communication to the Secretary*).-I have read with much interest the discussion of my paper by Arthur Knapp and I. N. Knapp published in the March Bulletin. These discussions apparently assume that my paper advances a. number of ideas that are not intended: 1. That the total sandbody or pay is to be removed. 2. That upon bringing this sand and oil to the surface 100 per cent., or perfect separation, can take place. 3. That this tremendous quantity of sand is then hauled away in wagons and distributed as road material. The paper raider discussion is not a theoretical treatment of the subject but is the result of actual experience in oil production under the conditions mentioned.. That wells that produce sand produce in ore oil, and the best operating methods to bring this about are fully treated. It is, of course, impossible to remove all the oil sand underlying a property, but the greater the amount removed the greater becomes the production of oil. As stated in my paper, the surface disposal of this large volume of sand is a problem and the only use to which it can be put is road surfacing; but I did not intend to convey the idea that all this sand was thus used. Only a very small quantity was required on the company's roads, and two wagons only were employed for this purpose. The remaining sand accumulated in the numerous "washes" and sumps. Although this sand contained sufficient oil to stain the hands, it was, surprisingly dry and could be easily shoveled. As stated in the paper, "the piles of sand are gradually freed of their oil content and a crust forms on their surface which will bear the weight of a man." I consider this a high degree of separation. A small amount of oil necessarily remains in the sand and is held there by capillarity. Otherwise it would be useless as a road binder, and, furthermore, to recover such oil special processes of treating are required. Arthur Knapp says, "of the total volume produced by pumping, not more than 4 or 5 per cent. can possibly be sand." I cannot agree with this statement as I have managed many properties where the wells were so operated that the amount of sand produced was five times this figure.

Jan 6, 1917

By J. E. Schaffer

Drilling activity in Ohio increased slightly in 1939. There were 1020 completions as compared to 910 in 1938. During the past six years the number of completions has varied little (Table 1). Oil production in Ohio has been gradually declining since 1896, when the peak production of 23,941,000 bbl. was reached (Fig. 1). Since that date production has slowly declined to an estimated production in 1939 of 3,144,134 bbl., the lowest in 53 years. This total production is divided approximately into the following grades of crude oil: Pennsylvania, 1,185,456 bbl.; Corning, 1,261,615 Flg 1. bbl.; Lima, 578,500 bbl.; Lodi, Based on figures of U. S. .Bureau of 104,740 bbl.; Cleveland, 13,823 Mines and Oil andGas Journal bbl. Table 2 shows the prices paid for the various grades of crude oil.

Jan 1, 1940

By George Schore

Radiation grafting of ion exchange structures contains ion exchange groups but may consist of neutral groups. High energy grafting of monomers on to polymers has-been known since 1950 (1.2); manufacture on an industrial level was-begun in 1970.(3) Proper choice of substrate and monomer will produce various ion exchange membranes with differing physico and chemical properties. Grafting a selected monomer to the proper polymer will provide selective ion exchange with assured chemical protection of the substrate. Ion exchange systems utilizing radiation grafted structures to polymers have been fabricated to "capture" gold from drag-out and rinse water and silver from cyanide rinse water. Other ion exchange systems can feasibly be produced to remove other precious metals. Rotating Cathode Technology is used to recover the metals from their concentrated eluating solutions as pure metal foil.

Jan 1, 1984

By J. E. Schaffer

Drilling activity in Ohio increased slightly in 1939. There were 1020 completions as compared to 910 in 1938. During the past six years the number of completions has varied little (Table 1). Oil production in Ohio has been gradually declining since 1896, when the peak production of 23,941,000 bbl. was reached (Fig. 1). Since that date production has slowly declined to an estimated production in 1939 of 3,144,134 bbl., the lowest in 53 years. This total production is divided approximately into the following grades of crude oil: Pennsylvania, 1,185,456 bbl.; Corning, 1,261,615 Flg 1. bbl.; Lima, 578,500 bbl.; Lodi, Based on figures of U. S. .Bureau of 104,740 bbl.; Cleveland, 13,823 Mines and Oil andGas Journal bbl. Table 2 shows the prices paid for the various grades of crude oil.

Jan 1, 1940

The 27th Regiment of Engineers was organized in the Army not long ago for special mining service at the front (or, we might even say, in advance of the front). In military engineering in warfare, the "sappers and miners" are one of the ancient branches of the corps of engineers; but in modern warfare the importance of this service has been greatly magnified. The 27th Engineers is a. special mining regiment, which is being recruited from mining engineers and miners from all districts of the country, already containing representatives from all the mining states between Arizona and Montana and from the Atlantic to the Pacific Coast. Those of us who cannot go to the front should not-be content to tell the young fellows to go, and then forget them. We want the men of the 27th Engineers to know that they represent our industry and their industry; and that the industry is going to think about them and back them up. Expressing the above views, the Engineering and. Mining Journal instituted a fund for the aid of the 27th Engineers. It has already raised a considerable sum of money, and contributions are coming in fast; but there is no limit to what is wanted. This money is being spent in providing the regiment with athletic equipment, both outdoor and indoor; with games for the barracks; with cigarettes and smoking tobacco; with contributions to the funds of the several companies that the men raise among themselves. It is contemplated, moreover, that there will be need to extend aid and comfort to some of the families whom the men have left behind. Contributions of books, sweaters and other knitted articles are also being received.

Jan 3, 1918

By John Birkinbine

Forty years ago, when the first shipments of iron-ore were made from the Lake Superior region, the supply for the blastfurnaces active at that date was in most cases a local consideration ; the majority of the smelting-plants being close to the oremines. Of those which depended in whole or in part upon ores brought from distances greater than an economical wagonhaul, few obtained supplies by canal or railroad from points 50 miles removed. At the present time the ore-supply is a local consideration for but a small proportion of American blast-furnaces, and 700 miles or more separate a greater num-

Jan 1, 1898

By William H. Emmons

Discussion of the paper of William H. Emmons, presented at the Canal Zone meeting, November, 1910, and printed in Bulletin No. 46, October, 1910, pp. 767 to S37. CHARLES R,. KEYES, Des Moines, Ia. (communication to the Secretary*) :-It is not in a spirit of criticism that I offer a supplemental suggestion or two on the subjects covered by this valuable and highly instructive memoir. There are two points which, in my opinion, should have received greater emphasis in Mr. Emmons's excellent paper. One is the fundamental role played by the chlorides under certain conditions in ore-formation. The other is the possible establishment of geographic relationships among the four phenomena of (1) excessive chloridic content of mine-waters; (2) the abundance of chloridic compounds of the precious metals ; (3) the presence of. manganese oxides; and (4) the diminishing importance, in ore-genesis, of the metallic sulphates. Although Mr. Emmons's notes refer to gold alone, it may be pertinently asked whether the same principles do not hold good for silver and copper also, since these metals form, together with gold, a distinct and well-known chemical group. That the reactions involved apply equally well to the other two metals mentioned, is shown by a number of recent observations and discussions. Chloridic ores of silver are, as I have lately endeavored to show, mainly worked in. arid or desert regions only ; and the great deposits of disseminated copper-ores are similarly characteristic of such regions, in which both classes doubtless owe their formation to the abundance of saline materials derived from desert dusts, and to the .plentiful and almost universal presence of manganese oxide. Under these climatic conditions, silver is somewhat more abundantly deposited than copper and gold, because its chloride is so much * Received Nov. 11, 1910.

Jun 1, 1911