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By David Baker

A Discussion of the Paper of David Baker, read at the Lake Superior Meeting, September, 1904. (Washington Meeting, May, 1905.) MR. JOHN J. PORTER, Chicago Ill. (communication to the Secretary*) :-Mr. Baker's account of his experiences with stock-distribution has been particularly interesting to me, as it confirms the opinions which I had formed concerning the rapid failure of linings in several furnaces that have recently come to my notice. These furnaces, four -in number, are of modern construction, having been built or remodeled within the past two years, and are equipped with a well-known type of skip-hoist and double-bell charging-apparatus. In every case, a hot spot has developed within a few months after blowing-in, which has already compelled relining in two cases, and the probabilities are strongly against a long campaign in the other two. Since the hot spot in each case appeared in a position approximately opposite to the skip-hoist, and since the sizing, mentioned by Mr. Baker, is very apparent, it would seem as though there could be no doubt concerning the cause of the trouble. Nevertheless, there are some who cannot see it in that light; for the managers of two of these plants, at least, do not admit the existence of bad distribution, and have satisfied themselves by putting in cooling-plates, thickening the lining of the in-wall, and changing the brand of the fire-brick used for the construction of the walls. From observations of the clumping-action of the skip-hoist, and from subsequent inspection of the stock-distribution in the furnace itself, I arrived at the conclusion, some time ago, that no system of filling could be perfectly satisfactory where the stock is dumped into the hopper from one side, also that some

Mar 1, 1905

By P. R. Sheorey

I read this interesting paper on pillar strength in some detail because this is also my area of interest. It has long been the desire of mining rock mechanicians to predict pillar strength from laboratory compression tests. Considerable literature is available on compression strength of rocks and coal but many of these experiments were conducted not for pillar design but for rock behavior. I have a few comments on the author's approach to pillar design, especially equation (33). Two important factors, which the author seems to have excluded, can be added to the right side of equation (2): time-dependence of strength and the influence of mine environment on strength (moisture and weathering.) The author has taken considerable pains to analyze a large amount of testing data in [Table 1], yielding the various exponents ci of equation (2) (or the subsequent equations derived from it.) He has, however, not shown by means of a worked out example how these values of [Table 1] could be applied to a practical pillar design situation. It would have been interesting to compare predicted pillar size using equation (33) with an actual case. Alternatively, equation (33) could have been used to explain the failure of a pillar, if such a case history were available. Consider we have a large number of case histories of stable and collapsed pillars in a seam and we conduct a large number of tests in a laboratory press. The exponents [ci] can then be determined for actual pillars as well as for test specimens. Thus, equation (2) will read [ ] Since laboratory testing conditions (e.g., between steel platens) are different from the conditions on pillars, the exponents [ci] in

Jan 1, 1983

By Alexander Bowie

IN many places throughout the Western mountain plateau regions of the United States coal beds in place have been burned over very extensive, areas, the fire evidently originating on the nakedly exposed outcrop of the coal bed and gradually burning its way into the bed for considerable distances under very heavy cover. . The surface evidences of the burned-out coal beds are seen in the calcined and discolored rocks overlying the places of the outcrop. The greater the mass of the burned coal the higher the results of its combustion can be seen in the overlying strata. I have noted many instances of this condition in the States of South Dakota, Wyoming, Colorado, New Mexico, and Arizona. In the lignite fields of Dakota and Wyoming I noted stretches of level country many square miles in extent where the surface rocks were roasted and vitrified by the burning of a great bed of lignite lying nearly level and with a light cover; this is probably the most favorable natural condition for the burning out of a coal bed. The less the depth of the rock covering overlying the coal bed, the better the .chance for a continuous supply of air to the fire; but when the coal bed clips heavily into the ground, or even if level, if it, passes under a hill or mountain which gives the bed a heavy covering of strata, the fire has more chances of being extinguished from natural causes than in the first condition described. The distance which, a crop fire may extend into a coal field is very much influenced by the dip, the thickness of the coal bed, and the nature of the rock covering immediately overlying it.

Jan 2, 1914

Discussion of the paper Of NOEL CUNNINGHAM, presented at the New York meeting, February, 1915, and printed in Bulletin No. 99, March, 1915, pp. 601 to 608. C. H. POIRIER, New York, N. Y. (communication to the Secretary*). -Mr. Cunningham's paper, written from the standpoint of a stamp advocate, while commenting more or less favorably upon the installation of ball mills in the Vipond plant, does not, in my opinion, give as much emphasis to the comparatively new departure as the installation of ball mills in the place of stamps justifies. This discussion is based upon my personal and intimate practical work for several years with stamp mills, and for the past three years with Hardinge ball and pebble mills. The fact that the Vipond mine contains about equal quantities of the A and B classes of ore mentioned by Air. Cunningham, and the further fact that I have had a most intimate knowledge of the working of both classes of ore in the Porcupine district in stamp mills and ball mills, justifies upholding my final decision to use ball mills in the place of stamps, and defends my present further action in now increasing the present Vipond capacity by the addition of another 6-ft. Hardinge ball mill, in which action the directors of my company concur. This is one of the strongest evidences I can possibly offer in substantiation of my opinion that the ball mill exceeds the efficiency of the stamp, both in metallurgical and mechanical economy. It is hardly fair to compare a 100-ton per clay plant with a mill handling several times this amount, yet it is my belief that the cost per ton. of grinding in the ball mill is far less than that of any stamp mill in the district, where capacities run up to 400 tons per clay.

Jan 5, 1915

By James Douglas

I had the good fortune to visit the Stockholm Exposition just before its close in October last, and to get a glimpse of the methods used in Sweden in making the wonderful steel and iron for which its furnaces are so famous. My time and opportunities for observation were limited, but some points which I noted may be worth bringing to the notice of the Institute. The Exposition itself was confined to the natural and artificial products of Scanclinavia, and therefore iron and steel held a very prominent place in it. There was a complete collection of the rocks and ores of the Peninsula made by the Geological Survey; and every iron-mine of note exhibited a glass model of its workings, as well as classified specimens, accompaniecl by thorough analyses of the ores. Another feature of interest was the display of models of the old mining-machinery, in the invention and introduction of which Sweden led the way, and of the old and new surveying-instruments and compasses devised for the exploration of the Swedish iron-ore bodies, all of which are more or less magnetic. The magnetometric collection and exhibit of methods of operation made by Prof. Nordestrijm were supremely instructive. The larger metallurgical works, such as those of the Kopparberg and Sandvik companies, exhibited their wares in separate pavilions, in which crude and manufactured objects were arranged most eflectively and tastefully; while the smaller companies erected in the Industrial Arts Building trophies, every one of which was an object of beauty. One was struck on all sides by the fine asthetic feeling exhibited in the ingenious installation of materials and objects not easily lending themselves to artistic treatment. Hammers, picks and drill-steel were grouped into mural designs which it was a delight to look at.

Jan 1, 1899

By Paul A. Beck

THE occurrence of the (100) [lOO] or "cube" texture upon annealing of cold-rolled copper has been much investigated.' The conditions favorable for its formation were found to be a high final annealing temperaturez or long annealing time," a high reduction of area in cold rolling prior to the final anneal,' and a small penultimate grain size." The effects of penultimate grain size and of rolling reduction were found by Cook and Richards4 to be interrelated in such a way that any combination of them giving lower than a certain value of the final average thickness of the grains in the rolled material leads to a fairly complete cube texture with a given final annealing time and temperature. Also, according to the same authors, at a higher final annealing temperature a larger average rolled grain thickness, i.e., a lower final rolling reduction, is sufficient than at a lower temperature. These somewhat involved conditions can be understood readily on the basis of recent results obtained at this laboratory. Hsun Hu was able to show recently by means of quantitative pole figure determinations that the rolling texture of tough pitch copper, which is almost identical with that of 2s aluminum: may be described roughly as a scatter around four symmetrical "ideal" orientations not very far from (123) [112]. In the case of aluminum, annealing leads to retain-ment of the rolling texture with some decrease of the scatter around the four "ideal" orientations, and to the appearance of a new texture component, namely the cube texture." A microscopic technique, revealing grain orientations by means of oxide film and polarized light, showed that the retainment of the rolling texture is achieved through two different mechanisms operating simultaneously, namely "re-crystallization in situ," and the formation of strain-free grains in orientations different from their local surroundings, but identical with that of another component of the rolling texture. Thus, a local area in the rolled material, having approximately the orientation of one of the four "ideal" components of the texture, partly retains its orientation during annealing, while recovering from its cold-worked condition, and it is partially absorbed at the same time by invading strain-free grains of an orientation approximately corresponding to that of another "ideal" texture component. The reorientation here, as well as in the formation of the strain-free grains of "cube" orientation, may be described as a [Ill] rotation of about 40°, see Fig. 1 of ref. 6. The preferential growth of grains in such orientations is a result of the high mobility of grain boundaries corresponding to this relative orientation.' " It appears very likely that in copper the mechanism of the structural changes during annealing is similar to that observed in aluminum (except for the much greater frequency of formation of annealing twins in copper). In both metals the new grains of cube orientation have a great advantage over the new grains with orientations close to one of the four components of the rolling texture. This advantage stems from their symmetrical orientation with respect to all four retained rolling texture components of the matrix; they are oriented favorably for growth at the expense of all of these four orientations. As a result, the growth of the "cube grains" is favored over the growth of the others, as soon as the new grains have grown large enough to be in contact with portions of the matrix containing elements of more than one, and preferably of all four component textures. It is clear that this critical size is smaller and, therefore, attained earlier in the annealing process if the structural units, such as grains and kink bands, representing the four matrix orientations are smaller, i. e., if the average thickness of the rolled grains is smaller. Hence, for a given annealing time and temperature, a smaller penultimate grain size and a higher rolling reduction both tend to increase that fraction of the annealing period during which the above condition is satisfied. Consequently, the percentage volume of material assuming the cube orientation increases. The same is true also for increasing time and temperature of annealing when the penultimate grain size and the final rolling reduction are constant, since the average size attained by the new grains during annealing increases with the annealing time and temperature. For the same reason, at higher annealing temperatures a given volume percentage of cube texture can be obtained with larger rolled grain thickness (larger penultimate grain size, or smaller rolling reduction) than at lower annealing temperatures. The well-known conspicuous sharpness of the cube texture may be interpreted as a result of the fact that selective growth of only those grains is favored that have an orientation closely symmetrical with respect to all four components of the deformation texture and exhibit, therefore, a high boundary mobility in contact with each. The effect of alloying elements in suppressing the cube texture, as described by Dahl and Pawlek,' appears to be associated with a change in the rolling texture. For face-centered cubic metals, such as copper, which do exhibit the cube texture upon annealing, the rolling texture is always of the type described above, i. e., scattered around four "ideal orientations" of approximately (123) [112]. The addition of certain alloying elements, such as about 5 pct Zn or 0.05 pct P in copper, has the as yet unexplained effect of changing the rolling texture into the (110) 11121 type. This texture consists of two fairly sharply developed, twin related components. In such cases, as in 70-30 brass and in silver, the annealing texture again is related to the rolling texture by a [lll] rotation of about 30°, however, because of the different rolling texture to start from, it has no cube texture component. At higher temperatures, both in brassm and in silver," grain growth leads to a further change in texture: A [lll] rotation of the same amount, but in reversed direction, back to the original rolling texture.

Jan 1, 1952

By Horace Pops

ThE shape of the primary solid-solubility limits in copper-rich Cu-Si-Zn alloys has been discussed recently1 in terms of the atomic size effects and the electron concentration, e/a. Although these limits are parallel to lines of constant e/a near the Cu-Zn binary system, they deviate and become sharply restricted near the Cu-Si binary system. Hence, it appears that the primary solid solutions with higher silicon contents are restricted by the presence of the intermediate phases, [, X, and p, which follow them in the ternary system. owever, a similar restriction in solid solubility might also result from an interaction in the copper matrix between silicon and zinc. Evidence for such possible interactions has been observed, for example, in the Al-Mg-Si systion.A where a contraction of lattice spacings in the ternary solid solution appears to correspond to an electrochemical interaction between the two solute elements, magnesium and silicon. The observed contraction is associated with restricted solid solubility. It was also shown1 that the extent of the primary solid solubility did not follow the trends predicted by the lattice-distortion oncept." This again suggested that the solubility limits are strongly affected by the stability of the intermediate phases, I, 1, and X . In order to test the above hypotheses, lattice-parameter measurements of the fcc @-phase alloys were determined within the ternary system at a constant electron concentration (e/a = 1.30) and also at a constant zinc content. Alloys of predetermined composition were prepared from high-purity metals and melted and cast under reduced pressures of helium in quartz capsules. Since the weight losses were very slight and did not exceed one part in 2000, the nominal compositions listed in Table I were accepted without chemical analyses. The ingots were homogenized

Jan 1, 1964

By William Metcalf

ONE of the first questions that naturally occurs to one who handles steel is," Why does steel harden ?" To answer this question the chemist and physicist have devoted much thought and experiment, and while they have enriched our store of knowledge of the nature and composition of steel, it cannot be said that they have yet solved the problem involved in its hardening. In this communication I desire to direct attention to a line of investigation yet new, in the hope that it may receive the attention of those who have the time and ability to pursue it. I refer to magnetism. There are so many parallels between the action of magnetism on iron and steel and their behavior under different processes of manipulation that it would seem as if there must be some connection between the forces at work in the different cases, if, indeed, there be not an identity of force in all of these cases. Magnetism, as we know it, may be merely the visible manifestation of forces, which may serve as a guide to lead us to an exact knowledge of the structure, the strains, and the resistances with which we have to deal in iron and steel. If a magnet be brought close to a pile of iron filings, the little pieces of iron will fly to the magnet and attach themselves to it, with their longer axes lying in the direction of the force. If molten cast iron be poured into an iron mould,-a chill,-the iron upon crystallizing will form needlelike crystals, with their long axes normal to the surfaces of the mould. If the iron is at the proper temperature and the quantity small, compared to the mass of the mould, the whole of it will be chilled, or set, in' the hard needlelike crystals

Jan 1, 1881

By AIME AIME

UNTIL recently, practically all geophysical prospecting in Australia was conducted by government departments, either by the Aerial, Geological and Geophysical Survey of Northern Australia or the New South Wales Department of Mines. At present, in addition, the Shell company is carrying out an extensive geophysical campaign in South West Queensland. The Northern Australia Survey has now been in operation for over six years, its work being carried out principally in the northern and central parts of Australia over an area of about a million square miles. At present this Survey is being brought to a conclusion but it appears certain that the geophysical section will be transferred to a Commonwealth Government department on a permanent basis. At present the officers of the Geophysical Section are preparing or have issued some 150 reports on their field work and also a special technical report on the geophysical practice of the Survey.

Jan 1, 1942

By AIME AIME

A METALLURGICAL research building is to be erected for the Armour Research Foundation at the Illinois Institute of Technology. It will be located at the corner of Federal and 34th Sts., Chicago, and fully equipped will cost $250,000. It will provide the Middle West with the largest and most complete of facilities for the conduct of developmental and industrial research in this field. The new building will be constructed around an existing foundry and metallurgical research building which has become too small to carry on and service the many research projects contracted for by the Foundation, having to do with steel, alloys, and nonferrous metals. After two bays of the new unit have been completed, the old unit will be torn down and the new one completed.

Jan 1, 1942

By J. S. Kirkaldy, G. R. Purdy

THE formation of ferrite in supersaturated aus-tenite has been the subject of considerable speculation and investigation. Aaronson has recently reviewed the data pertinent to this reaction.' Since these data in all cases refer to ternary or high-order alloys it is not possible to put them to the test of simple binary diffusion formalism. It has not, therefore, been possible to make a certain statement as to the controlling mechanisms in the process. An assessment of the difficulties inherent in the conventional statistical metallographic approach suggested that a study of the problem by means of a macroscopic two-phase diffusion couple might contribute useful information. Accordingly, such a couple was synthesized, and the rate of motion of a ferrite-austenite phase boundary (the growth of an austenite layer at the expense of a ferrite layer) was determined. Wagner originally produced a diffusion solution applicable to the motion of a planar phase interface in a binary diffusion couple, assuming local equilibrium throughout the diffusion zone. This solution, which is stated free of typographical error* in Ref. where a is the position of the interface in A space (A = x/fi), C; and CL1 are the equilibrium inter-facial concentrations in phases I and 11, C: and C*1 are the initial bulk concentrations in phases I and 11, and & and are diffusion coefficients (assumed constant). If a diffusion couple consisting of homogeneous layers of ferrite and austenite in equilibrium is raised to a higher temperature, the austenite layer will grow at the expense of the ferrite. Provided that the thickness of the ferrite layer is much less than the diffusion length of carbon in ferrite, we can set , so that Wagner's solution reduces to

Jan 1, 1963

E. R. Buckley, Flat River, Mo. (communication to the Secretary*) :—Some statements in the paper of Mr. Keyes relative to the nature and formation of the Ozark lead- and zinc-deposits seen1 to me erroneous and misleading, and I respectfully present the following criticisms, placing Mr. Keyes's original statements in quotations. Referring to the Ozark dome: (p. 192.) "It is a region that has been repeatedly upraised and planed off, until in the middle portion the oldest known rocks only are exposed." Does he mean that the St. Francois mountains, which have always been considered as lying on the eastern flank of the Ozark dome, are the middle of the dome ? Or does he mean that the Cambrian rocks of the generally-accepted middle are the oldest known rocks ? Certainly not the latter, and if the former, his idea of the middle of the dome is not in accord with that of others who are familiar with the region. (p. 203.) "... the ore-deposits are definitely associated with, or localized by, geologic structures of some kind that produce in effect basins in which the underground waters are impounded, or their flow retarded." This statement does not appear to be altogether consistent with the facts, since the ore bodies of the Joplin district, as the rule, occur in those parts of the Mississippian formation which have a tendency to accel erate the flow of ground-water rather than retard it. I migh name the open, brecciated ground near Joplin, Webb City, and Oronogo as especially noteworthy illustrations. The ore-bodies, everywhere, occur in positions where there must have been a free and copious circulation of dilute lead- and zinc-solutions in the presence of reducing constituents. The inequalities in the distribution of the ore-deposits are

Jan 1, 1910

By A. Adiassevich

PETROLEUM has been found in Russia in various localities from north to south, as may be seen from the list given below: (a) In the basin of the Petchora river, Northern Russia. (b) In the basin of the Volga river, in the governments of Samara and Saratoff. (c) In the government of Astrakhan and in the Uralsk territory, close to the northern and eastern coast of the Caspian sea. (d) At Grozny in Northeastern Caucasus. (e) In the Daghestan territory, Eastern Caucasus, on the Caspian sea. (f) On the Apsheron peninsula (Baku and other districts) close to the Caspian sea shore. (g) On the island of Tcheleken in the Caspian sea, also on the island of Sviatoi. (h) In the Transcaspian territory on the Neftianaia Gora (Oil hill) and on the surrounding hills. (i) In the Ferghana valley in Russian Central Asia. (j) On the Kertch and Taman peninsulas on the Black sea. (k) In Siberia it has been discovered in the Transbaikal territory and on the island of Sakhalin. In the above-mentioned districts petroleum has been found to exist under different geological conditions and to vary in its chemical and physical properties. At the present time petroleum is produced in Russia at Baku, Grozny, on the island of Tcheleken, in the Ferghana district, and in the Uralsk territory. The yearly production in 1912 throughout the Russian Empire amounted to 69,400,000 barrels, of which the Baku fields were responsible for 52,000,000 barrels. This shows that the Baku fields on the Apsheron peninsula are the chief oil-producing centers in Russia, being at the same time the oldest of all our oil fields.. In this paper I shall discuss the Baku fields only, leaving all the others until a later date.

Jan 5, 1914

By Herbert A. Everest

Discussion of the paper of HERBERT A. EVEREST presented at the New York meeting, February, 1916, and printed in Bulletin No. 109, January, 1916, pp. 165 to 167. NEWELL G. ALFORD, Earlington, Ky. (communication to the Sec-retary*).-Mr. Everest's statement concerning the economies in a small coal mine has interested me very much. The majority of discussions on coal-mine economy omit the small operator and for this reason Mr. Everest's paper should lead to productive thought. I agree that close concentration of working places and constructive supervision of labor are two items of salvation to the small operator. It is also true that small mines often yield as much profit per capital invested as their larger neighbors. Mr. Everest also says that the small operator has so keen a regard for the inroad on his profits that even one extra day hand is an extravagance not tolerated, and this is rightly so. But, does not this earmark of the small operator in many cases offer a clue to his vital weakness? A credit balance is the acid test of success in any enterprise. With the small operator who owns practically all the capital stock this is particularly significant. He never takes his eyes off the market price and at the same time strains every nerve to cut down his payroll. In several cases I have noted that the resultant close supervision of labor was in fact too close. The "stitch in time" was not applied to the repair of this or that, with a decided increase to the cost of the work when it had to be done at the expense of cutting off the run when orders were on the books.

Jan 5, 1916

By Morris Cohen, William P. Kimball

This paper deals with the calculation of the composition of the infinitesimal trace of alloy that transfers from the liquid to the solid state at each temperature during the equilibrium solidification of a binary solid solution, and which thereby enables the compositions of the coexisting liquid and solid phases to follow along the liquidus and solidus lines respectively during the cooling. A general expressioll for the composition (6) of the liquid-to-solid transfer at each temperature has been derived: , = Zlxl{xl - P) + ZsXsiP - xs) [I] Zl(xl -P)+ Zs{P - xs) where ZL and Zs are the slopes of the liquidus and solidus lines at the given temperature, xl and xs are the compositions of the stable liquid and solid phases at the same temperature, and P is the composition of the alloy under consideration. The d equation is valid for the process of equilibrium heating as well as cooling, and may be applied to vapor-to-liquid, vapor-to-solid, liquid-to-liquid, and solid-to-solid transfers if the corresponding equilibrium diagrams are known. The d-versus-temperature curves for two alloys P1 and P2 are shown in Fig. I. In each case, the liquid-to-solid transfer has the same composition as the stable solid phase only at the temperature of the beginning of solidification, and has the same composition as the stable liquid phase only at the temperature of the completion of solidification. At each intermediate temperature, the composition of the liquid-to-solid transfer differs by a finite amount from those of the two coexisting phases. Therefore, during equilibrium cooling. the transfers must merge into the solid phase from the liquid without forming a transition phase; otherwise the condition of equilibrium would be violated. At any given temperature during solidification, the composition of the liquid-to-solid

Jan 1, 1941

By William P. Kimball, Morris Cohen

This paper deals with the calculation of the composition of the infinitesimal trace of alloy that transfers from the liquid to the solid state at each temperature during the equilibrium solidification of a binary solid solution, and which thereby enables the compositions of the coexisting liquid and solid phases to follow along the liquidus and solidus lines respectively during the cooling. A general expressioll for the composition (6) of the liquid-to-solid transfer at each temperature has been derived: , = Zlxl{xl - P) + ZsXsiP - xs) [I] Zl(xl -P)+ Zs{P - xs) where ZL and Zs are the slopes of the liquidus and solidus lines at the given temperature, xl and xs are the compositions of the stable liquid and solid phases at the same temperature, and P is the composition of the alloy under consideration. The d equation is valid for the process of equilibrium heating as well as cooling, and may be applied to vapor-to-liquid, vapor-to-solid, liquid-to-liquid, and solid-to-solid transfers if the corresponding equilibrium diagrams are known. The d-versus-temperature curves for two alloys P1 and P2 are shown in Fig. I. In each case, the liquid-to-solid transfer has the same composition as the stable solid phase only at the temperature of the beginning of solidification, and has the same composition as the stable liquid phase only at the temperature of the completion of solidification. At each intermediate temperature, the composition of the liquid-to-solid transfer differs by a finite amount from those of the two coexisting phases. Therefore, during equilibrium cooling. the transfers must merge into the solid phase from the liquid without forming a transition phase; otherwise the condition of equilibrium would be violated. At any given temperature during solidification, the composition of the liquid-to-solid

Jan 1, 1941

By Stephen Taber

JOHN C. BRANNER, Stanford University, Cal. (communication to the Secretary *).-Wideawake teachers of geology are constantly on the lookout for good illustrations of veins, especially where the processes of formation are either clearly shown or suggested. And I long ago found out that one who would learn nature's laws must despise nothing. It thus happened that in 1910, Dr. George J. Peirce of the depart-ment of botany at Stanford University called to my attention a cracked and broken yellow earthenware dish, 8 ½ in. across the top and 2 ½ in. deep, that, to the ordinary observer, seemed to be of no further use, and quite ready for the waste can. The striking thing about this dish was that the thin glaze over much of the outside surface and over the upper margin of the inside surface had been lifted in small scales, varying in. diameter from ½ cm. to 1 cm., and thrust outward and held there by some sort of white fibrous mineral. The process looked very much like one we are familiar with in the Southern States where. we often see in the winter pebbles and soil thrust out from a clay bank or lifted from a clay soil and held there supported by what is popularly known as needle-ice. Upon inquiry I learned the following facts in regard to the history of this particular dish: In the summer of 1910, it had been partly filled with a concentrated salt solution taken from one of the salterns of the Stauffer Chemical Co. at Redwood City, Cal. A qualitative analysis of the original brine showed: Present: iron, magnesium, sodium, potassium, chlorides, sulphates, nitrates (trace), bromides, carbonates, borates (trace), and considerable amounts of organic matter. Absent: calcium, lithium and iodides.

Jan 3, 1917

By Persifor Frazer

IT was my intention to have directed the attention of the members of the Institute to a complete series of rocks representing the older and middle formations represented in Pennsylvania, but time has been insufficient for the purpose, and I have been unable, in the first attempts to reduce the sections of those rocks, which I have brought with me to this meeting, to the requisite thinness necessary for exhibiting the peculiarities of their constituent minerals. The rocks represented here belong to the various horizons already mentioned, and include gneiss, ferruginous gneiss, chlorite slate, quartzites, and hydro-mica slates, limestones, dolomites, ferruginous conglomerates, quartz conglomerates, "Potomac marble" (nether member of the Mesozoic series), dolerites, and a syenite. The order in which these are named is, roughly, the order -of geographical position in a section line from southeast to northwest, commencing at the intersection of the Northern Central Railroad with the Maryland line, and ending a few miles from the town of York, and a short distance within the marginal outcrop of Mesozoic red sandstone. In such a geographical section all the rocks above mentioned would be encountered in the given order except syenite, about which a few words are to be said in a moment. (But this is far from representing the rocks in their geological sequence.) There is nothing of unusual interest to present to your notice in these slates and quartzites. The limestones were carefully searched under 450 diameters microscopic power, but they show no signs of organic remains. One section of a fine-grained Triassic sandstone contains a very beau¬tifully banded plate of quartz. But the objects of greatest interest at present are the specimens of trap. The more fine-grained and compact traps were collected from

Jan 1, 1875

FINAL REPORT OF' THE COMMITTEE OF THE AMERICAN INSTITUTE OF MINING AND METALLURGICAL ENGINEERS W. E. FOHL, Chairman J. W. PAUL J. M. RAYBURN C. A. WARNER JOHN B. CORRIN C. E. KREBS JOHN H. WILSON A. W. HESSE M. M. LEIGHTON H. I. SMITH [Accepted and Committee discharged with thanks, April 27, 1928.] Regulations recommended for the location, drilling, casing, protection, operation, plugging and filling, and abandonment of natural gas and petroleum wells; having for their objectives the protection of life and property by prevention of intrusions of oil and gas into workable coal beds, and the conservation of oil and gas resources in territory not underlain with workable coal beds. ARTICLE I DEFINITIONS SEC. 1. For the purpose of these regulations, definitions are as follows: Well.-A bore hole drilled for the purpose of developing natural gas or petroleum, or a bore hole producing natural gas or petroleum. Well Operator.-Any person, persons, firm, partnership, corporation, company or association that proposes to, or does drill, operate or abandon a well as herein defined. Coal Operator.-Any person, persons, firm, partnership, corporation, company or association that proposes to, or does operate a coal mine in territory known or reputed to be underlain with oil or gas-bearing strata. Coal Owner.-Any person, persons, firm, partnership, corporation, company or association, other than a Coal Operator as herein defined, that owns coal lands in territory known or reputed to be underlain with oil or gas-bearing strata. State Mining Department.-The duly constituted authorities of a state having jurisdiction over coal-mining operations, and oil and gas operations as herein provided. Plat.-A map, drawing or print made in accordance with the provisions of these regulations. Casing.-The pipe commonly used in wells drilled for natural gas and petroleum. Oil and Gas.-Synonyms, respectively, for Petroleum and Natural Gas.

Jan 1, 1928

By Meredith Johnson

THE year 1924 saw little change in the production of oil and gas it either Pennsylvania or New York. In the early months of the year the price of Pennsylvania crude oil, $4.00 to $4.50 a barrel, was sufficiently high to cause operators to lay plans for rather extensive drilling opera-tions. But when, in August, the price dropped to $2.85 a barrel, there was no inducement for new work and drilling was curtailed. In spite of the curtailment, however, the combined production of the two states for the year showed a slight increase over 1923, the production being 8;859,000 bbl. in 1923, and 8,901,000 bbl.1 in 1924. The increased production was due entirely to. the continued development of flooding operations in the Bradford field, all other oilfields showing a decline for the year. TABLE 1. Production of Crude Oil in Pennsylvania and New York for the Last Ten Years a Production, Barrels Production, Barrels Year Year Pennsylvania I New York Pennsylvania I New York 1915 7,838,000 888,000 1920- 7,438,000 906,000 1916 7,593,000 874,000 1921 7,418,000 988,000 1917 7,733,000 880,000 1922 7,425,000 1;000,000 1918 7,408,000 809,000 1923 7,609,000 1,250,000 1919 8,137,000 851,000 1924 7,535,0006 1;366,0006 a U. S. Geological Survey figures. b Estimated. Much of the drilling in the southwestern part of Pennsylvania was done in search of gas. Natural gas in Pennsylvania is fast being recognized at its true worth and the increased prices allowed 'the gas companies for their product induced quite a bit of new work. The relative importance of natural gas compared with manufactured gas is shown in Table 2.2

Jan 3, 1925