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The passing of Benjamin Bowden Lawrence in January, 1921, was a distinct loss to the engineering profession. Mr. Lawrence had a genius for reviving abandoned mines and developing them into substantial producers. A notable example of his work in this line was the Dives-Pelican near Georgetown, Colo. While on an exploring expedition in 1888, he examined this old mine and was convinced that bonanza ore still existed there. He located the owners of the property, and induced them to place sufficient capital at his disposal to enable him to re-open and explore this mine. So confident was he of the outcome that he undertook this work on a profit-sharing basis without salary. Within eighteen months the old Dives-Pelican was operating profitably, and for the following ten years it paid very substantial dividends. The late Theodore N. Vail was one of the owners of this old mine, and many years later, at a dinner given to Mr. Lawrence by the Alumni of Columbia University, Mr. Vail told the story of the resuscitation of the Dives-Pelican by Mr. Lawrence, and declared that the dividends he himself had received provided a large part of the funds that made possible the realization of his dream of establishing the long-distance telephone in this country. The E1 Cobre mines at Santiago de Cuba also owed their renewed life to Mr. Lawrence. Under his management, these mines produced and shipped several million pounds of copper per year. He was for several years consulting engineer for the Kerr Lake and other silver mines in the Cobalt region; the Kerr Lake became famous as a silver producer. Mr. Lawrence spent more than twenty years of his life in the mining camps of the West. He was but twenty-one years of age, and only a few months out of college, when he was appointed manager of the great Chautauqua Lode (a silver mine) located on Glacier Mountain near Montezuma, Colo. Here, isolated in the mountains for several months each year by ice and snow, he worked for five years to make these mines Pay. He possessed unusual breadth of vision and human understanding; he had ''personality plus," and when he opened an office in New York City as consulting engineer he quickly rose to an enviable position in his profession. Young engineers worked with enthusiasm under his guidance. He carefully selected his men, discussed fully with them the plans and policies to be pursued, then left them free to accomplish results in their own way. This attitude developed individuality and resourceful-

Jan 1, 1922

William B. Cogswell, member of the Institute since 1872, died on June 7, 1921, at his home in New York City, after an illness of about six weeks occasioned by an infection of the middle car. Mr. Cogswell is survived by his wife, Mrs. Cora Brownell Cogswell; a son-in-law, and three grandchildren. His first wife died in 1877. William Cogswell was born at Oswego, Sept. 22, 1834, and was taken to Syracuse by his parents when he was four years old. He attended Hamilton Academy and private schools in Syracuse and Seneca Falls. In 1843, he visited England with his parents and brought back a set of drawing instruments, which led to a series of lessons in architecture under Luther Gifford, the only architect in Syracuse at the time. The boy drew many building plans and one set was used for the old Globe Hotel in Syracuse, erected in 1846 and 1847. In 1848, when only 14, he spent a year with a party that was surveying the route of the Syracuse & Oswego R. R. and relaying the tracks of the Utica & Syracuse R. R. He studied civil engineering at the Rensselaer Polytechnic Institute, Troy, for three years, but left that institution in 1852 without receiving his degree. Many years later, in 1884, the degree of C. E. was conferred upon him. During the three years following 1852, Mr. Cogswell served as an apprentice in machine shops at Lawrence, Mass., under the superintendence of John S. Hoadley. About 1856, he was made manager of the machinery department of the Marietta & Cincinnati R. R., at Chili-cothe, Ohio, and three years later became superintendent of the Broadway foundry at St. Louis, Mo. In 1860, in Syracuse, Mr. Cogswell was associated with William A. and A. Avery Sweet in the formation of Sweet Bros. & Co., which later became the Whitman & Barnes Mfg. Co. At the outbreak of the Civil War, Mr. Cogswell received a civilian appointment as mechanical engineer in the United States Navy. During 1860 he was located at Port Royal, S. C., having general supervision over the work of fitting up repair shops at five widely separated stations on the Atlantic seaboard and Gulf of Mexico. In this year his genius and resourcefulness were notably shown. He literally launched a naval machine shop, so that warships could be repaired without leaving, and thereby weakening, blockades against Southern ports. The machine shop was assembled by Mr. Cogswell and shipped by boat to Port Royal. There an old whaler was made over for machine shop purposes and Mr.

Jan 1, 1922

The officers and staff of the Petroleum Division are the servants of the members, and to the extent that the wishes of the members are made known and are practicable they will be carried out. The tentative plans outlined here are in general accord with previous custom, but modified by suggestions received recently from various members. The advice of all members is solicited, and it is hoped that the general expression on matters of policy can soon be facilitated by circulation of a questionnaire. Plans for two mid-year meetings of the Petroleum Division and for participation in the annual meeting at New York were inaugurated at the last annual meeting and are being carried forward as rapidly as possible in the belief that an early start will increase the possibility of finding the best available program material and permit the careful preparation, review, editing, and advance discussion of papers. While a number of papers have already been solicited, both members and nonmembers are hereby invited to submit additional papers, with the assurance that such papers will be given just as favorable consideration as the papers that have been requested. Mid-year meetings will be held at about the same time both in the Mid-Continent and California. The time will be selected if possible to coincide with the visits of President Lovejoy, who expects to be in California the last of September and in Texas early in October. Fort Worth, Dallas and Austin have been suggested for the Mid-Continent meeting. The Pacific Coast meeting will be held at Los Angeles. It is to be noted particularly that a Pacific Coast meeting was waived last year in favor of the annual meeting of the American Petroleum Institute, which was held at Los Angeles for the first time in nine years. It is hoped, and it was the understanding at the time among a number of individuals interested in both organizations, that in view of this action of the Petroleum Division the industry will give more than the usual support to the A.I.M.E. meeting this year. Ultimate Recovery is being considered as the keynote topic for the mid-year meetings. In view of trying financial conditions combined with an exceptionally high current potential rate of production, it is natural that the attention of the industry should be focused upon means of controlling production and reducing cost of operation. It seems that the Petroleum Division of the A.I.M.E., as a professional group, might

Jan 1, 1936

By T. R. Armstrong

During the year 1939, Mexican production totaled 42,479,000 bbl.; a daily average of 116,381 bbl. or a little over 2 per cent of the estimated world production. The Mexican Government operates 100 per cent of the refining branch of the industry, 100 per cent of the domestic distribution, 96 per cent of the crude production and 92 per cent of the total exports. No discussion of the Mexican petroleum industry in 1939 is adequate without reference to the "expropriation" of the foreign-owned oil properties in Mexico by executive fiat on March 18, 1938. The forcible seizing of the properties culminated a long series of efforts on the part of the Mexican Government to obtain control of the oil properties developed through foreign initiative and with foreign capital in Mexico. The heart of the issue is whether the Mexican nation or any nation may with impunity confiscate the legally acquired properties of American citizens. The Department of State of our Government has in its communications to Mexico emphasized the fact that its "expropriation" of American properties was confiscatory because Mexico had failed to make "adequate, effective and prompt compensation"; that the taking was no less confiscatory "because there may be an expressed intent to pay at some time in the future," and that, consequently, "Mexico has assumed and continues to assume to exercise a right without compliance with the condition necessary to give such exercise a recognizable status of legality." Mexico has professed its willingness to pay for the oil properties but at the same time through its Supreme Court it has declared that the owners or lessees do not have the exclusive right to extract and dispose of the oil in the subsoil. This is a reversal of the Mexican position with respect to oil as set forth in the Mexican mining laws, affirmed by Mexican Supreme Court decisions, and as clarified in the Warren-Paync and the Morrow-Calles agreements, as well as in diplomatic correspondence. Efforts to Settle the Controversy Responding to suggestions from the State Department, representatives of the principal oil companies undertook in 1939 to effect a direct

Jan 1, 1940

By Sylvain J. Pirson

The main value of earth magnetic measurements, outside of certain mining problems, resides in the study of deeply buried tectonic phenomena related to regional and local geology. Magnetic surveys are a necessary complement of gravimetric measurements, especially of pendulum surveys. To date, magnetometer prospecting has been used chiefly in the study of sedimentary basins where petroleum structures are associated with the uplifted basement rocks. There are, in the literature, innumerable articles dealing with such surveys as applied to oil geology but few treat of broad geological features related to regional magnetic disturbances of the earth field. An important piece of coordination work has been made by Jean Jungl for the magnetic and gravimetric measurements made in France and their geologic significance. A similar attempt at correlation of the known geology with the anomalies of the vertical component of the earth magnetic field has been made for the United States by George B. Somers2. Taking the magnetic vector as a whole, W. P. Jenny3 made a coordination of magnetism and geology for the main producing oil states of the United States. A more detailed study along the same lines is published by A. Van Weelden4 for southern Oklahoma and northern Texas; in this work magnetic and gravimetric measurements taken at stations as close as one mile apart are compiled and compared to the regional geology of the Ouachita-Amarillo uplifted area. From the literature mentioned, it is evident that reliable interpretation of magnetic' anomalies can be arrived at only when the magnetic stations are numerous and cover the area in a close net of measurements, therefore the works of Somers and Jenny, based on sparsely distributed Government measurements, can be regarded only as preliminary programs indicating lines along which further work should be done, whereas the coordination made by Van Weelden is an example of the contribution to the knowledge of regional geology that can be arrived at by the use of applied geophysics. With the hope that further systematic magnetic measurements will be carried on to solve regional and local geological problems, the author

Jan 1, 1940

By Sylvain J. Pirson

The main value of earth magnetic measurements, outside of certain mining problems, resides in the study of deeply buried tectonic phenomena related to regional and local geology. Magnetic surveys are a necessary complement of gravimetric measurements, especially of pendulum surveys. To date, magnetometer prospecting has been used chiefly in the study of sedimentary basins where petroleum structures are associated with the uplifted basement rocks. There are, in the literature, innumerable articles dealing with such surveys as applied to oil geology but few treat of broad geological features related to regional magnetic disturbances of the earth field. An important piece of coordination work has been made by Jean Jungl for the magnetic and gravimetric measurements made in France and their geologic significance. A similar attempt at correlation of the known geology with the anomalies of the vertical component of the earth magnetic field has been made for the United States by George B. Somers2. Taking the magnetic vector as a whole, W. P. Jenny3 made a coordination of magnetism and geology for the main producing oil states of the United States. A more detailed study along the same lines is published by A. Van Weelden4 for southern Oklahoma and northern Texas; in this work magnetic and gravimetric measurements taken at stations as close as one mile apart are compiled and compared to the regional geology of the Ouachita-Amarillo uplifted area. From the literature mentioned, it is evident that reliable interpretation of magnetic' anomalies can be arrived at only when the magnetic stations are numerous and cover the area in a close net of measurements, therefore the works of Somers and Jenny, based on sparsely distributed Government measurements, can be regarded only as preliminary programs indicating lines along which further work should be done, whereas the coordination made by Van Weelden is an example of the contribution to the knowledge of regional geology that can be arrived at by the use of applied geophysics. With the hope that further systematic magnetic measurements will be carried on to solve regional and local geological problems, the author

Jan 1, 1940

By Richard McCaffery

THIS paper considers certain aspects of the acid Bessemer process, particularly in its relations to the duplex process-that combination in which the pig iron is first desiliconized and decarburized in acid Bessemer converters and then dephosphorized in basic open-hearth furnaces. The acid Bessemer process employs an acid-lined converter and produces an acid slag. The blow is usually thought to eliminate the silicon and manganese as oxides and then to burn off the carbon as carbon monoxide. On account, however, of the relatively large amount of metallic iron present in the converter, compared with the relatively small amount of the impurities it is desired to oxidize, the first reaction in the converter probably is the formation of iron oxide, which dissolves in the bath and acts as an oxygen carrier for the silicon and carbon. As soon as iron oxide is dissolved throughout the bath, the oxidation of silicon commences; but in the early stages of the blow the mass law would indicate that iron oxide must form first, and this oxide probably increases up to some saturation point. The molten metal in the converter from the early stages of the blow right through to its completion remains basic, while the slag produced is siliceous. This fact is shown by the corrosion of the acid bottom and the tuyeres, which is greatest at the tuyere orifice where oxidation is most active and where there is the most iron oxide. Why does this acid bottom corrode? Because it is attacked by a base. The thought, therefore, suggests itself, why not make the bottoms of basic or neutral material?1 As the converter slag is acid, those parts of the converter coming in contact with the slag should be acid; but those parts of the converter that are in contact with the molten metal saturated with metallic oxides should be basic or neutral. Bessemer operators have for some time tacitly admitted this condition, for the blast pressures have steadily increased with the object of keeping the metal in suspension, and so preventing bottom corrosion; if the molten metal were not basic, it would not attack an acid bottom. In addition, the tuyeres are bunched together at the middle of the bottom and a clear space is left around the outside of the bottom; if tuyeres are placed too near the side walls the

Jan 8, 1920

Without doubt Arizona was the scene of the first use of coal in North America, that by the Hopi Indians as early as the 10th century in burning their pottery and in heating their houses and kivas (ceremonial rooms). As has already been said this is the only use of coal by Indians of which we have any knowledge, but it has been well established through investigations conducted by the Peabody Museum of Archaeology and Ethnology of Harvard University. The apparatus for burning was crude, but they did have fireplaces and chimneys which would draw. The evidences of coal use were found in the Jeddito Valley, in Navajo County, during the excavation of the pueblo of Awatovi, only a short distance from the Keams Canon School. "Many fire pits and primitive stone stoves containing coal ash have been found in the houses, and in most of the kivas built between 1300 and 1600, two firepits have been found, one containing wood ash exclusively and the other coal ash."' The expedition of 1939 found that coal was used much earlier than this, as stated above. It is probable that these Indians were using coal regularly before it came into general use in England and northern Europe. Apparently the use of coal was largely stopped about the time the Spaniards came to that country. The ruins are located on the southern edge of the Black Mesa and the coal seams outcrop on the mesa edge below the ruins. "The coal occurs principally in one large seam which varies from a foot and a half to six feet in thickness."1 This coal is sub-bituminous and burns well, leaving a large percentage of white ash. Another seam is found about 40 ft. above this large seam; it is from six inches to a foot thick and burns to a red ash. Both of these seams were used and coal from the larger seam was used at other houses in the valley. The pottery was usually burned close to the coal seams, and the coal was used to obtain a uniform and satisfactory color. In the Jeddito Valley, the mining was done by stripping, and the methods used are described as follows by J. 0. Brew and John T. Hack, the investigators.

Jan 1, 1942

By J. E. Warren

In their analysis of Eqs. 29 and 30, the authors correctly deduce the following behavior limits for the "differential capacitance model". 1. When the rate group a is sufficiently large, the model reduces to that implied by Eq. 1, i.e., the simple convection-diffusion model. 2. When the rate group a is sufficiently small, the model reduces to that implied by Eq. 1 with 1 replaced by 1, i.e., the simple convection-diffusion model with a total pore volume equal to that occupied by the mobile fluid in the original model. Unfortunately, the authors' solution, Eq. C-1, to the transformed versions of Eqs. 29 and 30 does not exhibit the same limiting behavior. For example, as a approaches zero, Eq. C-1 reduces to the solution to Eq. 1 or, equivalently, the solution to Eqs. 29 and 30 for sufficiently large values of a. Therefore, it can be concluded that Eq. C-1 is not a general solution to Eqs. 29 and 30; this conclusion can be easily verified by substitution. I suggest that the correct form of Eq. C-1 is the following: It is generally realized that accounting for dispersion effects is an extremely tricky business; therefore no one should criticize the pragmatic approach of Coats and Smith who proceeded by accessible theory, made use of some available phenomenology, and who then took the trouble to check the consequences, against their own carefully undertaken experimental results. Here I should like to defend three assertions: (1) Coats and Smith copy the error of previous authors in the formulation of the so-called simple diffusion model (which error is then retained in their differential capacitance model); (2) improving the fit between data and the predictions of an arbitrary model by increasing the number of parameters is a triviality unless the parameters are disposable by being independently determined; and (3) existing experimental procedures lack sufficient resolution to clarify some current theoretical uncertainties. Taking first the view that all theoretical approaches (whether constructed by statistical, finite difference, or continuum arguments) tend to reduce to the same model form as fixed by the number and nature of the disposable parameters, one notices that the "finite-stage" model of Deans1 is equivalent to the Coats and Smith so-called differential capacitance model for the pertinent case where a

Jan 1, 1965

By J. W. Harden

AT our meeting in October last we saw in operation at Pittsburgh, the comparatively modern process of the utilization of small coal by washing, by an arrangement similar to that of Bérard or Morrison. The small coal washed was that of an old pile, the refuse of the mining of the Pittsburgh bed, and which had long lain uncared for. Value was thereby restored to it when it was converted into a very good coke. This circumstance led to comments on the mountains of broken coal lying wasted, and in its present condition worse than useless, in the neighborhood of the mines of the Wyoming Valley, though they are not confined to that district. Some things were said condemning the course which produced it, some were left unsaid. Of a system that destroys one-half the coal-bed in producing the other half there can, however, be but one opinion. Schemes have been suggested for the utilization of present accumulations which, if successfully applied, would in so far be beneficial. More than ordinary attention is now being given to the same subject in England; a Mr. Barker has invented a means by which he amalgamates the "dust," too fine to burn in ordinary grates, with a composition he calls "diamond cement," producing blocks of coal said to resist water, both hot and cold, and which a smart blow will only break to pieces, not cause to crumble. But any scheme less than the one which will prevent the wasting of coal, which still goes on, though that involves the abandonment donment of the breaker, will only be one of expediency; and the latter can only be done by the aid of the consumer. But the wasting of coal is not alone with the breaker ; much is made in the mine. The cause is not far to seek ; the remedy is with capitalist and owner. Owners and consumers then are alike interested, and they have it in their power, in the one case, to mitigate, in the other, almost entirely to remove the cause of the evil. Of consumers there is one in every

Jan 1, 1873

The production of petroleum in India (including Burma) increased from 334,811,624 gal.' ill 1936 to 350,322,222 gal. in 1937, the highest figure in the history of the industry. The increase in 1937 was clue to an increase of some 20 million gallons from Singu, 51/2 million gallons from Attack, 11/4 million gallons from Thayetmyo, and 1 mi1lien gallons from Digboi, accompanied by decrcases of 91/2 million gallons from Yenan-gyaung and 2 million gallons from Yenangyat,. The amount of gasoline produced from natural gas during the year was 10,616,313 gal. in Burma and 456,780 gal. in the Punjab. Yenangyaung Field.—The Yenangyaung field maintained its reputation of being one of the most wonderful oil fields in the world. The total production during 1937 was less than in the previous year but the resources of the field as a whole are sufficient to ensure an adequate supply of oil for many years. At the end of 1037 there were 2910 wells producing in the field. Besides a large number of ells drilled to shallow sands, this total includes 180 hand-dug wells, whose continued existenice is one of the interesting features of the field. During the year the deep drilling activities of 1936 in the southern part of the field died down, owing to the disappointing results obtained. On the eastern flank the limit of present economic extension of the oil sands was approximately demareated. Satisfactory results continue to be obtained from gas drives in the leased blocks; gas is also injected for repressuring and storage. Casing policies continue to be carefully designed to protect the oil sands against the danger of flooding by water and, in general, production methods throughout the field are characterized by a realization of the importance of the conservation of oil and gas and the prevention of waste, whether simple or underground. Singu Field.—-In 1937 the increase in the output from the Singu field was continued. This increased production was due not only to the rapid development of the valuable area in the southern part of the field but also to the successful results obtained from the first wells to produce from behind the practically completed river training wall of the Burmah Oil

Jan 1, 1939

By Charles Legrand

The problem of mine pumping is so much affected by local conditions, and those conditions are so liable to changes during the life of a mine, that the best system to use is difficult to determine. The experience of the writer has been that, in general, for copper mines, electric pumping is most satisfactory unless the quantity of water to be pumped is great or the mine does not use electric power for any other purpose. As a rule, however, figuring on the cost of necessary power plant, the total cost of installation is greater with electric pumps than steam pumps. As the water is liable to be gritty, outside-packed plunger pumps are to be recommended, and if the water is not acid, or only slightly so, chilled cast-iron plungers pay for their extra cost very quickly in diminished cost of packing. With chilled plungers it is possible to use metallic packing instead of soft packing, if the water is not too gritty or the lift too high. In vertical pumps this packing is satisfactory for lifts up to 400 ft., in the experience of the writer, and may be found satisfactory for higher lifts. For water slightly acid, cement-lined pump bodies have given good satisfaction. For acid water, both plungers and puhp bodies should be made of acid-resisting bronze. For high lifts, especially with gritty water, a satisfactory pump valve is difficult to find. To reduce the unbalanced pressure on the valve at time of opening it is advisable to have narrow seats; this, however, brings high pressures on the seats when the valve is closed. On large valves for lifts of 600 to 1,000 ft. we have used leather, hard rubber, vulcanized fiber, and soft brass; for clear water the latter has given best satisfaction. The difficulties due to grit make it advisable to have large sumps where water can settle, and if possible, to have two of them so that they can be cleaned alternately. At the mines of the Old Dominion Copper Mining & Smelting Co., Globe, it was found that a small air ejector discharging into a mine car provides a very convenient way to clean mud and sand from a sump.

Jan 1, 1916

By Charles M. Ryder

In presenting this paper to the Institute I beg to mention, first, the results which I have obtained and the apparatus which I have employed, and to follow this with a brief description of the steps by which I hare perfected this process. My present mode of testing is as follows: I obtain, either from the furnace or from the finished product in any stage in which it may chance to be, a small test-piece, usually about 3/4 of an inch square by 3 1/2 inches in length. I place this test-piece upon the poles of an ordinary electro-magnet, for about one minute, and thus magnetize it to its extreme limit. I then place it upon an indicator (which I will shortly describe), on which indicator there is already placed a piece of steel of similar form which has been magnetized in the same manner, the percentage of carbon of this second piece being definitely known. I then, by means of a scale, which forms part of the indicator, marked in degrees of carbonization, read the exact percentage of carbon contained in the piece under examination. My apparatus consists of an ordinary electro-magnet, connected with a suitable battery of moderate power, by which I magnetize the pieces as before described, and of an indicator which consists of a magnetic needle suitably mounted or suspended, so that it is free to deviate a few degrees only from the zero point, and having a rest, which is used to check the vibrations when in use, and to support its weight when not in use. At a right angle to the natural position of the needle I have a scale about 3 feet long, the zero point of which coincides with the natural position of the needle. This scale is marked in each direction from the zero point in degrees of carbonization. The marking of the scale is in accordance with the following rule: Taking the carbonization of the steel as a basis, I maintain the same proportion between the squares of the distances on the scale as exists between the percentages of carbon in the steel, for instance, if .08 of

By R. A. Pallanch

Sodium sulfite as a zinc retarding agent in the selective Hotation of complex lead-zinc sulfide ores was discovered by the writer in the summer of 1919 in the testing laboratory of the U. S. Smelting, Refining & Mining Co.'s gravity concentrator at Midvalc. Utah. It proved to be the first reagent to give consistently good results in the laboratory on the cornpanj's Bingham ore. In December, 1919, C. A Lemke, concentrator superintendent, recommended that a flotation unit be added to the existing gravity mill to handle the mill slimes, using sodium sulfite as the zinc depressant Owing to the poor lead and zinc markets and the unfavorable royalty schedules offered by the Minerals Separation Co., the project fell through at this time. In 1921, a number of laboratory tests were made at Midvale. on other ores, among them ore from the Sunnyside mine at Eureka, Chlo. Both sodium and calcium sulfites were used with succcss on this ore. Early in 1923, further tests were made at Eureka, shortly after the Sunnyside company had resumed operations after a two-year shutdown. AS a consequence sodium sulfite was given a trial in the mill. The results showcd sufficient improvement over previous work as to warrant continuous use of this reagent in the lead circuit Exeept for a week or so in 1926 and for several weeks in April, 1927, when sodium cyanide and zinc sulfate were given trial runs in this mill. sodium sulfite has been used ever sinee.. Sodium sulfite was chosen rather than the calcim sulfite brcauscl of its gre1ater sollubility, making it possitdr. to introduee the reagent as a solutiun. This Solution is introdueed into the Marry ball mills along with the original feed of ore,. The consumption of sodium sulfite in the Sunnyside mill varies from 1/4 to 12 lb per ton of ore, the smaller amount probably being nearer the average. In February, 1924, laboratory work at Midvale demonstratcd conclusivcly that good results could be obtaincd on the company's Bingham ore and on most of the custom ores tested by using sodiuin sulfite as the zinc depressant, xanthate as the lead enhancer in the lcad circuit, followed by copper sulfate and additional xanthate to float the zinc Sodium sulfide was used to float the iron pyrite after the lead and

Jan 1, 1928

By Tracy Jarrett

THE alloying of various elements with gold to produce different colors is an old art, but the effect of each element or combination of elements is not generally known. Investigations have been made in this field by F. E. Carter,1 E. M. Wise,2 and L. Sterner-Rainer.3 It is the intent of this paper to present in schematic diagrams the effects of various ele¬ments upon the color and the melting point of gold alloys. In this investigation 2-oz. melts made in a high-frequency induction furnace were used for all tests. The melting points were determined by the use of a calibrated chromel-alumel thermocouple sealed in a thin-walled alundum tube. The couple was then submerged in the molten metal and the freezing and melting points were determined by using a Leeds and Northrup potentiometer. By checking several melts using copper, zinc and gold, it was found that the accuracy of determining the melting point was within ± 5° F. To determine the differences in colors and to classify them, a wet tissue paper was placed over the polished samples and examined under a uniform white light. The 2 by ½ by 0.045-in. samples were cut from 50 per cent cold-worked strip. The original ingot was 3 by ¼ by ¾ in. This visual comparison, although not scientifically exact, served as a quite satisfactory means for determining and classifying these differences. The base alloys, or "hardeners," were first made up and analyzed, after which the gold and silver were added. This method of making up the alloys was chosen so that the same base alloy could be used for the gold alloys of different karats. The first series consisted of gold, copper, zinc and nickel, the copper comprising from 85 to 65 per cent of the content of the "hardener" and the zinc and nickel replacing copper. The second series consisted of gold, silver, copper, zinc and nickel, the copper comprising from 85 to 65 per cent of the content of the hardener with the silver, nickel and zinc replacing copper. There was no particular reason for choosing these combinations, except that they gave a color range from red-pink to white.

Jan 1, 1939

By S. Shapiro, G. Krauss

We will reply to Dr. Pitsch's discussion by 1) presenting in greater detail the single surface trace analysis which we performed on the reversed austenite plates in a single parent plate of martensite of known orientation, 2) relating the results of our analysis to the conclusions which Dr. Pitsch makes on the basis of our data, and 3) examining the validity of our selection of twenty-nine individual traces from the over 200 austenite plates which were observed in a surface of this single martensite plate. Fig. 7 shows a standard (001) projection of the martensite plate from which the austenite-martensite interface traces were taken. The traces are plotted on the projection as the small solid circles, and the great circles corresponding to the loci of plane normals which could contain each trace or could intersect the surface plane along the measured directions are also plotted. It can be seen that these great circles intersect at a point which corresponds to the normal of the surface plane on which the traces were observed. Also rate which occurred only at particularly low heating rates, see Figs. 1 and 3 in the paper.2 Since in this case the interpretation of Jana and Wayman is plausible and since we have no alternative to this interpretation, we would like to state only that the existence of a diffusion-controlled reversal at low temperatures seems to be not yet proved beyond any doubt. The author wishes to thank Professor G. Krauss for making available his manuscript prior to publication. It is also a pleasure to acknowledge the lively written discussions, which the author has had with Professors G. Krauss and C. M. Wayman prior to this communication. The financial support of the Deutsche For-schungsgemeinschaft for the work on which this communication is based is also gratefully acknowledged. plotted within small dotted circles which represent a i3 deg scatter in each of the twenty-four unit stereo-graphic triangles are our A and B poles7 and the pole P determined by Kessler and itsch.' The data presented in Fig. 7 permit a direct association of the measured traces and the various proposed habit plane poles for the reversed austenite plates in the martensite crystal. If the sample measurements do in fact

Jan 1, 1969

By H. C. George

Since 1911, when J. L. Dunn first used compressed air for repressuring depleted oil sands in southeast Ohio, the rejuvenation of many depleted oil fields has been directly due to repressuring by means of air or gas. Developments in repressuring in recent years have resulted in its successful use in the early life of some deep, high-pressure oil fields, conserving the natural gas dissolved in and associated with the oil by returning it to the producing oil sand after it has been compressed above the existing rock pressure of the reservoir. One of the most successful operations of this type is that of the Humble Oil & Refining Co., on the DeWalt salt dome at Sugarland, Texas. I quote from a personal communication with reference to this field: "Structurally, the field is dome-shaped, having a closure of approximately 350 ft. Production comes from a sandy shale interbedded with a clean sand and lying over a cap rock which is about 3400 ft. deep on top of the structure." A feature of the operation of this field is the production of the required amount of oil with the minimum of gas production. Wells on top of the dome have high gas-oil ratios, while those down structure have lower ratios, depending upon the distance of the well from the peak. To date, it has been possible to produce the oil needed from the wells circling the dome above the water zone and below the gas zone, and in this manner the average gas-oil ratio has been kept low. The gas from all separators is turned into a gas system which serves the entire field. From this system, all drilling rigs and utilities requiring gas for a fuel draw their requirements, and the remainder of the gas (about two-thirds of the production) is delivered to a compressor plant which boosts the pressure until it can be returned to the sand at the top of the dome where the rock pressure is 1400 lb, per square inch. "The Sugarland wells produce through 2-in. tubing with a 3/8-in. choke in one wing of the well-head manifold. The pressure builds up as high as 1300 lb, per square inch on the casing while on the tubing it varies from 0 to 900 lb. per square inch, depending upon the amount of gas produced with the oil."

Jan 1, 1931

By A. Lee Barrett

THE Maintenance Committee of the Coal Division of the American Institute of Mining and Metallurgical Engineers is presenting as a part of this report the second of a series of maintenance cost comparisons. The committee's purpose is to assemble maintenance costs on all equipment connected with mechanical operations at the face of coal mining and to arrange these costs by districts so that comparisons can be made between districts and within districts. The committee, this year, sent 35 questionnaires to representative coal companies who either reported last year or had advised specifically of the inability to report to last year's questionnaire primarily because of limited time. The response to the questionnaire this year was not as good as last year, only 20 of the 35 selected companies returning a completed questionnaire. This year's data has been .compiled and combined with last year's data to present a comparison of the 1945 and 1946 costs of loading machines, shortwall cutting machines, universal cutting machines, service locomotives, shuttle cars, and mine cars. The same tabulation by districts is used as was used for 1945. As was indicated by last year's report there is considerable variation in the maintenance cost of mining machinery in the various coal mining districts and due to this high variability it was not felt practical to attempt to Arrive at weighted averages. Consequently, all average figures used in this report are straight averages. An analysis was made of companies reporting both this year and last year in an attempt to determine the trend in maintenance costs for different classes of equipment. Ten representative companies are used in this computation. Table I shows the average cost for 1945 and 1946. It is felt that the negative trend in the maintenance cost of universal cutting machines probably represents the effect of the purchase of a relatively large number o new machines in 1946 with little maintenance cost appearing during the first yeas of operation. The grand total figure indicates an upward trend amounting to plus 18.7 pct. However, this figure is viewer with some suspicion because of the effect of the universal cutters decreasing maintenance cost and it is concluded that direct application of percentage increase should be made to types of equipment. In Table 2 covering maintenance costs of various types of mining equipment for 1945 and 1946 the results, obtained in Table I indicating trends were applied to those

Jan 1, 1948

By F. V. Lenel

R. P. Seelig.*—Dr. Lenel is to be congratulated on his presentation of a particularly interesting paper describing the use of the powder metallurgy process for the production of magnetic pole pieces. The only thing that might be added is that we have been successful in producing pole . pieces with a narrow hysteresis curve by the use of considerably lower sintering temperatures than the ones used by Dr. Lenel. It is quite possible that this use of lowe- temperatures has considerably widened the field of commercial application for pole pieces made from metal powders. Development work is currently being done on an a.c. application of a sintered iron part. However, I am in full agreement with Dr. Lenel that if eddy currents are an important factor in the application, we cannot substitute sintered material for laminated sheet-metal structures. Mr. Peters' remarks concerning the limitations of machine parts were well taken. The emphasis of the limitations makes it easier to define clearly what we can do and-what the advantages are of machine parts made of metal powders. When I mention metal-powder machine parts, I mean those of relatively high density, although complete elimination of porosity is not possible at this time. The limitations of the field for this type of parts are largely economical. I believe that Mr. Langhammer has made that point very clear. The following questions are very often asked: How large a part can you make? How close can you hold the dimensions ? How fast can a part be produced? In a majority of the cases, it depends on the cost at which the part can be produced. A large variety of shapes and sizes of a number of materials can be formed. However, the main requirement in this field of endeavor is whether this can be done more economically by powder metallurgy than by other manufacturing methods. As a general indication, it may be stated that densities up to 95 per cent of that of rolled material can now be produced commercially in simpler parts. Tolerances of plus or minus 0.001 in. are common, but where special conditions justify, closer tolerances can be held; we are producing a part of which one dimension is held to 0.0003 inch. Finally, as far as maximum size is concerned, technically this would depend on the capacity of the press and furnace equipment available. Actually, we find that the economical limit of powder-metallurgy machine parts is approximately one pound. From there on, each individual case must he studied on its own merits.

Jan 1, 1945

By Earl Oliver

THE term oil property, in this discussion, includes any type of easement or grant under which petroleum might be produced; it ranges from the mere right to drill on undeveloped wildcat acreage up to a fully developed oil property. The values of an oil property, as thus defined, vary widely according to the use for which it is intended, whether it is from the viewpoint of the speculator, the fraudulent stock promoter, the refiner and pipe-line owner, or the oil producer. The market value of a property is usually a combination of some two or more of these influences, and occasionally a combination of all of them, but we prefer to treat each viewpoint as distinct from the others, allowing the reader to make his own combination in such proportions as his inclination and property seem to require. This paper will treat the subject from the viewpoint of the oil producer. However, the other influences have such bearing on the cost of property to the producer and on the price he might obtain by its sale as to warrant brief discussion of them. Speculation, particularly lease speculation, is a parasitic growth on the oil industry, healthy enough, but of no economic value. The class of property usually dealt in for this purpose is the undeveloped lease. Its speculative value may have some relation to its probable productive value, but most frequently this value is the product of temporary excitement due to local development. The lease speculator, seeking out the trend of development or securing early information regarding a proposed test or a new discovery, immediately secures leases whose market value will be increased when the existence of such development becomes more widely known. His profits are purely unearned increment. Not proposing to spend money in exploration, he can afford to compete in purchase with the operator, who, in addition to bonus paid, must spend large sums in testing out his own acreage and that of the nearby speculator as well. It has a tendency to compel unduly high bonuses.

Jan 2, 1920