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By Lewis T. Wright

(Pittsburg Meeting, March, 1910.) I HAVE long been aware that ferruginous copper furnace slags if fused in the electric arc will yield metallic iron containing copper, and in order to confirm this knowledge, and to obtain further information of the behavior of such slags in the high temperature and reducing conditions of the electric furnace, a number of samples of slag were fused in an experimental electric furnace. The results obtained, given in Table I., show that a very large amount of metallic iron was produced, and that this iron carried with it practically all the copper, gold, and silver, and more than 50 per cent. of the sulphur, of the original slag. The metallic buttons formed in the electric furnace were clean, hard, but not brittle.

Mar 1, 1910

By Irwin Roman

In studying the possibilities of a continuously recording magnetometer for use along the surface of the earth and in an airplane, the Federal Bureau of Mines was led to a study of the theoretical resolving power of magnetic observations, both in the variation of the total magnetic intensity and in each of the two cornponents ordinarily measured. Along with this general study, an attempt was made to determine the relative worth of the total intensity anomaly and the vertical anomaly in geophysical prospecting. Genera1 considerations led to three conclusions: I. In the northern magnetic hemisphere of the earth, the total intensity anomaly is offset to the south of the vertical anomaly, for a positive anomaly (see Appendix, note 1). 2. The resolving power of magnetic observations decreases rapidly with distance from the disturbing body. 3. The horizontal anomaly has little value in prediction of the disturbing body but might be useful in making a choice between bodies suggested by the vertical or total anomaly. Some of the considerations leading to these conclusions were: I. The normal intensity and the anomalous intensity are vectorially additive; hence for a positive anomaly in the northern magnetic hemisphere the total intensity will be a maximum at some point south of the disturbing body and north of the point at which the line to the disturbing body is parallel to the normal earth's field. The anomaly itself has a maximum value directly above the body. For a positive anomaly of constant magnitude, the total intensity will be a maximum when the anomaly vector is parallel to the normal vector. This is shown schematically in Fig. I (not to scale) for a magnetic distribution not restricted to a relatively thin sheet in the magnetic meridian. The normal field has a magnitude 10 with vertical component V0 and horizontal component Ho. Six station points along a traverse across the body from south to north are shown at M to S. At each of these stations the normal magnetic field vector terminates at F. At each of these stations the magnetic field vector due to the disturbing body B terminates at A. The line through the station point and the point A passes through B. The magnitude of the anomaly, indicated by the length of the vector terminating at A, is proportional to some power of the distance from the station point to the disturbing body. If the disturbing body B is a concentrated point of magnetic material, the anomaly is proportional to the inverse second power of the distance. For a uniform magnetic distribution over a line perpendicular to the observed traverse, the anomaly is proportional to the inverse first power of the distance. For surface distributions, the law of intensity is more complicated. At each field point, the total magnetic intensity T is the vector sum of the

Jan 1, 1949

Discussion of the papers of DAVID H. BROWNE, Louis V. BENDER, and R. E. H. POMEROY, presented at the New York meeting, February, 1915, and printed in Bulletin No. 97, January; 1915, pp. 49 to 60, 73 to 81, and No. 98, February, 1915, pp. 445 to 453, respectively. E. P. MATHEWSON, Anaconda, Mont.-After hearing about the success of D. H. Browne with his furnaces, we in Anaconda decided we might venture into the field of pulverized coal for reverberatory smelting. We sent a delegation of investigators to see Mr. Browne and his work, and they returned, filled with enthusiasm, and said they would recommend it strongly. We thereupon asked for an appropriation, and after some delay obtained the same and fitted up one furnace to use pulverized coal. We copied Mr. Browne's practice and his selection of machinery for drying and pulverizing coal; and we also copied the burner he used, which was a standard article on the market. We got an expert coal-dust machinery man to design our plant, and were very glad we did so as we avoided some of the unpleasantness that had been experienced at other plants through fires and minor explosions.

Jan 5, 1915

THE 127th meeting of the Institute was held in New York, Feb. 19 to 22, 1923. In addition to the usual large volume of technical matters under consideration, the meeting was particularly noteworthy for the amount of attention given to its business session; the convention of local section representatives also was full of interest. The total registration was 1201. The annual business meeting on Feb. 20, President Dwight presiding, was attended by 125 members, who listened with marked attention to the reports and addresses of the several officers. The chairman departed from the stipulated order of business in order to allow more time for the presentation of remarks on the state of Institute affairs. The previously pub-lished reports of the officers were accepted, as printed. On the report of the tellers, the following officers were declared elected: E. P. Mathewson, Director and President-District 0 T. T. Brewster, Director and Vice-president-District 6 Frank M. Smith, Director and Vice-president-District 11 W. H. Aldridge, Director-District 0 G. H. Clevenger, Director-District 1 A. N. Diehl, Director-District 3 Reno H. Sales, Director-District 7 Seeley W. Mudd, Director-District 10

Jan 3, 1923

The following is a partial list of members and guests who called at Institute headquarters during the period July 10, 1917, to Aug. 10, 1917: G. A. Collins, Seattle, Wash. Norman Picot, Melbourne, Aust. A. D. R. Galloway, Komfrodua, W. Africa. W. E. Pomeroy, El Paso, Tex. F. Lynwood Garrison, Philadelphia,; Pa. Francis R. Pyne, Elizabeth, N. J. Geo. M. Henderson, Bland, N. M. W. L. Remick, W. Norfolk, Va. L. B. Herr, Jr., So, Bethlehem, Pa. M. F. Sayre, Schenectady, N. Y. Zay Jeffries, Cleveland, 0. Leighton Stewart, New York, N. Y. H. H. Lauer, Allentown, Pa. Randolph D. Talmage, Joplin, Mo. Wm. B. McKinlay, Yonkers, N. Y. H. J. Volker, Ossining, N. Y. A. N. Mackay, Republic of Colombia. Dwight E. Woodbridge, Duluth, Minn. Edmund Newton, Minneapolis, Minn. Kwong Wu, Peking, China. J. N. Acosta has resigned his position as mining engineer for the Shannon Copper Co., Gleeson, Ariz., and is now engaged as consulting engineer for Lower California, Mexico, with headquarters at San Diego, Cal. L. D. Albin, formerly assistant general sales manager of the Ingersoll-Rand Co., was appointed general sales manager on July 25,1917.

Jan 9, 1917

Committee. ROBERT H. RICHARDS, Chairman. ALBERT SAUVEURr Vice-Chairman. AUGUSTUS H. EUSTIS, Secretary-Treasurer, 131 State St., Boston, Mass. TIMOTHY W. SPRAGUE. HENRY A. WENTWORTH. The thirteenth meeting of the Boston Local Section was held at the Engineers' Club, 2 Commonwealth Avenue, Boston, on Monday evening, Oct. 6, 1913. Fourteen members and three guests were present at the dinner, at which Chairman Robert H. Richards presided. After the dinner, the Chairman expressed his pleasure in welcoming the members at the first dinner following the vacation. He said that lie had attended a meeting of the Directors of the parent society in New York ; that they had asked what the Boston Section were doing, and expressed their hope that we would be able to make some of our papers formal and offer them for publication. The Chairman then said that lie realized the objection to this; that members were less willing to speak for publication than informally, but that lie hoped, nevertheless, that some of the speakers this year would see their way to write up a formal paper at some later date, along the general lines of their informal ,addresses.

Jan 11, 1913

As is known to representatives on Engineering Council, the Patents Committee of Council has collaborated with the similar committee of National Research Council in developing a scheme for the improvement of the method of dealing with patents in this country. The staff of the Patent Office is itself actively engaged in this effort. Out of the report prepared by the National Research Council, and approved and adopted by Engineering Council as the report also of its Patents Committee, remedial legislation has taken form. Three hills have been introduced, known as H.R. 5011, a bill to make the Patent Office independent of the Department of the Interior or any other department, and to simplify the procedure of the Courts with reference to assessment of damages or profits for infringement of patents; H.R. 5012, a bill to establish a single Court of Patent Appeals; and H.R. 7010, a bill to increase the force and salaries in the Patent Office. Chairman Charles A. Terry, of the Patents Committee, requests that representatives of Engineering Council write to their congressmen, urging the passage of these hills and so far as convenient, request their friends to do likewise.

Jan 9, 1919

C. P. SANDBERG, LONDON, ENG : † I think we should all be grateful to the Pennsylvania Railroad Company, and to their chemist, Dr., Dudley, for spending so much time and money in order to solve an important question ; nor are we less indebted to the public spirit which leads them to impart the experience thus gained. In Europe nothing similar has hitherto been done, either by a company or by any private individual. In England the great railway companies employ their engineers in other ways, and do not keep a chemist or specialist to study rails; but even if they did they would probably not publish the results. The chief professional engineers are so occupied with their private practice of railroad construction generally, that they cannot be expected to devote their time and energies to so special a question. The German Railway Union has, in my opinion, missed the real object of its elaborate researches by falling into the error of specifying costly, impracticable tests for rails-tests at the same time which do not infallibly expose the impurities that may be in the rails under examination. There has, therefore, been nothing done on this side of the Atlantic in the way of exhaustive study to determine the best composition for steel rails. America should consequently have full credit for the enlightened example which she has set. I wish, however, to make a few remarks on Dr. Dudley's second paper, a paper which follows very much upon the same lines of argument as the first read three years ago, upon which I have previously touched in my paper on the same subject read at the meeting in August last. If Dr. Dudley had discovered a new metal he could hardly, I think, have taken more pains to prove that he was correct in his first formula for the best chemical composition of steel rails. But I have seen so much done in the way of proof by experiment that I am inclined to think that almost anything can be proved by experiments and by samples. If Dr. Dudley would only give up his formula, which would not suit any country-not even America- * For the convenience of members it has bees thought best to insert the continuation of this discussion at the Virginia meeting in tide place, rather than to delay its permanent publication until the issue of Volume X, Transactions, where it would properly belong. T. M. D., Sec'y, † Sent to the secretary in manuscript.

Jan 1, 1881

By R. D. Mollison, C. F. Fogarty

Sulfur is widely distributed in nature. It is present in the earth's crust, the ocean, the meteorites that come to us from cosmic space and in practically all animal and plant life. According to Clarke,9 the earth's crust contains 0.06 pct sulfur. Large quantities of free or combined sulfur are found in coal, natural gas and petroleum. Mineral waters contain sulfates and hydrogen sulfide. Sulfur is rather plentiful in the crust of the earth; however, only under special circumstances can it be produced profitably. Sulfur is one of the cheapest raw materials used by industry; and, therefore, the economic feasibility of a given deposit is strongly dictated by the law of supply and demand on local as well as world-wide levels. The forms which are commercially important are elemental sulfur or brimstone, and the sulfides such as pyrite (FeS2), pyrrhotite (FenSn+1), chalcocite (Cu2S), sphalerite (ZnS), and galena (PbS); the sulfates such as gypsum (CaSO4,2H2O), anhydrite (CaSO4), and kieserite (MgSO4,H2O). Elemental Sulfur Elemental sulfur is found in many localities, generally in solfataras and gypsum type deposits. The solfatara deposits are found commonly in the neighborhood of active or extinct volcanoes as in Italy, Japan and Chile, or fumaroles associated with mineral springs such as the Mammoth Hot Springs in Yellowstone Park. Here the sulfur is deposited in tufas or other porous host rocks. This type of sulfur deposit probably results from the oxidation of hydrogen sulfide or the reaction of hydrogen sulfide with sulfur dioxide. Most of the world's supply of elemental sulfur comes from the gypsum-type deposits. Here the mineral occurs as either crystalline or amorphous sulfur in sedimentary rocks in close association with gypsum and limestone. This association is characteristic and occurs in almost all the great gypsum beds of the world, although sulfur is not always present in quantities of economic importance. Various theories have been advanced to account for this association. Bischof5 suggested that the sulfur came from hydrogen sulfide which resulted from the reduction of calcium sulfate by carbon or methane in accordance with the following reactions: CaSO4 + 2C= CaS + 2CO2 CaS + C02+ H2O = CaCO3 + H2S CaSO4 + CH4= CaS + C02+ 2H20 2H2S + 02= 2H20 + 2S All of the sulfur-bearing domes on the Gulf Coast have calcium sulfate in great quantity in the cap. They all show the presence of hydrocarbons. The oxygen for the final reaction could have been supplied by circulating ground waters. The principal objection to this theory is that temperatures of 700° to 1000°C are needed to reduce the sulfate to sulfide with carbon compounds. The geologic evidence is that the temperature of the sulfur-bearing domes of Texas did not exceed 100°C. Proponents of the theory say that geologic time or a catalyst replaced temperature. According to another theory the sulfur in the salt domes is the result of bacterial action. Sulfate reducing bacteria have been detected in sulfur cores and in the formation water issuing from salt domes. It has, therefore, been suggested that these bacteria converted the sulfate to sulfide which subsequently was converted to elemental sulfur.

Jan 1, 1960

By Frederick Laist

0. C. RALSTON, Salt Lake City, Utah.-I have merely glanced over this paper, consequently, I am hardly in a position to discuss it intelligently. There is one thing, however, that is of interest, that is, the claim that the oil mixture which they have chosen is the best adapted to the work at hand. I would like to ask Mr. Mathewson if they still feel that that is the case-if that really does give the best grade of concentration and the best extraction for the same money, compared to any particular oil mixture which they could get. E. P. MATHEWSON, Anaconda, Mont.-We are still using that mixture, and we consider it the most economical mixture used. DAVID COLE, El Paso, Texas.-I would like to ask Mr. Ralston if there are some other mixtures that would be better? E. P. MATHEWSON.-We are open to suggestions. 0. C. RALSTON.-My own paper on oils* calls attention to the fact that certain hardwood oils, especially the tars, are now being burned or wasted. A great deal of hardwood tar is available as low as 4 or 5 c. per gallon, that being its value as fuel under the boilers. As a matter of fact, a great deal of testing has been done with only the commercial products that are as a usual ride sold on the market. Very little hardwood tar is sold on the market. In asking a great many people who have tested flotation oils, I have not heard hardwood tar mentioned very often. I think I would add to that that the hardwood tars can probably be bought in quantity comparable with the sludge acid at Anaconda, and. should contain a greater proportion of the frothing constituent, and at a price fairly commensurate with what they pay for the sludge acid. E. P. MATHEWSON.-I would like to make a correction in one statement I made that there has been no change made in the mixture. This change has been made: We found that the amount of wood creosote in treating the sand from tables was extremely small, and we tried some experiments on a large scale, dropping it out and using simply the sludge acid and sulphuric acid. We found that this gave practically as good results as wood creosote. We use wood creosote in treating the slimes. We find it necessary in that operation. DAVID COLE.-I would like to ask, what is sludge acid?

Jan 10, 1916

MINING AND METALLURGICAL SOCIETY OF AMERICA San Francisco Section The San Francisco Section of the Mining and Metallurgical Society of America held a joint meeting with the local section of the American Institute of Mining Engineers at the Engineers' Club, San Francisco, on Tuesday, Apr. 16, 1918. The meeting was preceded by a dinner. Letters from the parent body in NewYork asking for the consideration of the proposed bill before Congress, and an expression of opinion relative to the appointment of a Federal Administrator of Mines justified the joint meeting of the local sections of the two mining societies, in that a more representative opinion of the engineers of California could he obtained. The meeting was called to order at 7:15 P.M. by Mr. Frank H. Probert acting as Chairman. About thirty engineers were present. Mr. Probert read a letter of March 14, from Secretary Huntoon, asking that the meeting be called. He read excerpts from Bulletin 117 of February 28, 1918, of the Mining and Metallurgical Society containing a copy of the proposed bill, so that all present might be advised of its essential contents. He briefly commented on the urgent need of such legislation and invited discussion of the subject. After long and thorough discussion on the part of the members present, Professor Lawson made the following motion: I move that a resolution expressing the sense of the joint meeting of the local sections of the American Institute of Mining Engineers and Mining and Metallurgical Society of America be forwarded to the secretaries of the two societies to the effect that we heartily approve of the purpose and intention of the bill designed to promote and stimulate the production of minerals necessary for the successful prosecution of the war; and that we suggest prices should be fixed for the period of the war and two years thereafter, and that these prices, guaranteed by the Government, should apply at the nearest shipping point to place of production of the minerals. This motion was carried. The meeting then adjourned, and a telegram was sent by Mr. Probert, the Chairman, to Mr. Huntoon, notifying him of the motion that had been carried at the meeting.

Jan 7, 1918

New York Meets first Wednesday after first Tuesday of each month. DAVID H. BROWNE, Chairman. PERCY E. BARBOUR, Vice-Chairman. A. D. BEERS, Secretary, 55 Wall St., New York, N. Y. C. A. BOHN, Treasurer. Boston Meets first Monday of each winter month. W. E. C. EUSTIS, Chairman. - R. L. AGASSIZ, Vice-Chairman E. E. BUGBEE, Secretary-Treasurer, Mass. Inst. of Technology, Boston, Mass. ALBERT SAUVEUR, H. L. SMYTH. Columbia Holds four sessions during year. Annual meeting in September or October. STANLY A. EASTON, Chairman. FREDERIC KEFFER, Vice-Chairman. LYNDON K. ARMSTRONG, Secretary-Treasurer, P. O. Drawer 2154, Spokane, Wash. D. C. LIVINGSTON. FRANK A. ROSS.

Jan 12, 1916

By M. Takeda, H. Majima

Pyrite has been subjected to xanthate adsorption experiments in order to determine the nature of adsorption. The identification of adsorbed species by means of IR spectroscopy, as well as UV, shows that the dixanthogen adsorption is undoubtedly predominant on pyrite surface. The rest potential measured in a xanthate solution coincides with the redox potential of the xanthate-dixanthogen couple. Considering all the factors together, the adsorption mechanism of dixanthogen on pyrite has been proposed as This mechanism is consistent with the "passive" character of pyrite. From the measurement of the redox potential of the xanthate-dixanthogen couple in the homologous series, a rule similar to that for surface tensions proposed by Traube is also applicable. The polarization experiments were conducted on pyrite in a solution containing xanthate. In the anodic polarization, xanthate is observed to oxidize to dix- anthogen, which depresses oxygen evolution on py rite at higher potential levels. In spite of the importance of the presence of pyrite in the flotation of sulfide minerals, not many studies have been made on the xanthate-pyrite system in the absence of an activator or a depressant. In an early study by Gaudin and Wilkinson,' it was pointed out that no ferric xanthate was formed on a pyrite surface, while in another study Gaudin and his collaborators2 proved the formation of a very small amount of ferric xanthate. Afterwards, Gaudin et al.3 studied the pyrite-xanthate system with a radiometric technique and found indications of the presence of adsorbed dixanthogen on pyrite surfaces. Mamiya4 studied the flotation behavior of the pyrite-xanthate system and also suggested the possibility of dixanthogen. Recently, Fuerstenau and his coworkers at The Colorado School of Mines5 studied the role of dixanthogen in the xanthate flotation of pyrite and discussed the problem in terms of such properties as oxidation potential, zeta potential, flotation recovery, pH of solution, etc. However, the mechanism of dixanthogen adsorption at the pyrite-water interface is not yet understood. This paper is concerned with an electrochemical in-vestigation through which the mechanism of dixanthogen adsorption on pyrite is interpreted. EXPERIMENTAL MATERIALS AND TECHNIQUES Pure potassium xanthates were synthesized by an

Jan 1, 1969

By F. Julius Fohs

With portions of two coal basins within its borders and a few scattered fields already developed, the question arises: What is the future of Kentucky as an oil-producing State? Is the long list of failures due to lack of commercial pools, or unintelligent prospecting? A study of its beds and irregularities of structure points not only to a large waste of development money on unpromising areas, but also to the presence of a few structures well worthy of development. The surface rocks of Kentucky show in succession more than 4,000 ft. of Paleozoic sediments and more than 2,000 ft. of Cretaceous, Tertiary, and more recent deposits. Folding and erosion have brought these beds to the surface, where they have been observed and studied in detail by my associate, James H. Gardner, myself, and others. This has given opportunity to observe the beds offering suitable reservoirs and having the proper impermeable covering; also the mapping of outcrops and outcrop lines, taken in conjunction with available well records, indicates that certain areas are worth testing, and with even greater definiteness shows areas which should be excluded, as devoid of possibilities. West of the Tennessee River, Cretaceous, Tertiary, and Quaternary sediments occur so that all trace of ancient folding is obliterated, the sediments overlapping unconformably Mississippian rocks. This area embraces 2,000 square miles, or one-twentieth of the area of the State, the Paleozoic rocks covering the remainder. Since there is nothing upon which to base the location of tests for oil and gas in the Cretaceous-Tertiary beds of Kentucky, the Paleozoic area will be chiefly considered. The distribution of Paleozoic rocks in Kentucky is centered about the north-northeast striking Cincinnati geanticline, bringing to the surface on the Jessamine dome the oldest rocks exposed in the.State, those of the Devonian, Silurian, and Ordovician systems. On either flank of this great earth-arch are the Mississippian rocks, sloping gradually beneath the coal-measure basins to the west and to the east. West of the western coal basin, and. between it and the Cretaceous-Tertiary rocks further west, is a high area of Mississippian rocks. Crossing the State

Jan 1, 1915

By Clarence Thom

This chapter presents, in summarized form, standard procedures for making separations of minerals from their ores by the froth flotation process to produce marketable concentrates. These are typical mineral separations which are being made commercially with the reagents and conditions generally used in the mining industry. Typical separations are presented for 17 metallic and 11 nonmetallic ores. The review of each includes a brief description of the mineral and the particular problem presented, general market specifications for its concentrates, an outline of treatment method, and kinds and quantities of reagents usually employed. This chapter does not include de- tails about ore preparation (crushing, grinding, and classification), elements of ore and pulp transportation (conveying and pumping), or concentrate preparation for market (thickening, filtering, and drying). In each presentation it is assumed, if not detailed further, that the ore is ground to the economical point of liberation of the minerals to be separated. Specific information, such as ratio of concentration and recovery, that depends upon the grade of ore being treated is considered beyond the scope of this chapter. Effective flotation separations that produce marketable concentrates may produce widely varying results in terms of percent recovery and still be economically profitable operations. Details of plant practice on specific ores are presented in Chapters 16 and 17. In this chapter the chemical names of the reagents are given. The extent to which different reagents are used in flotation plants in the U. S. is presented in Chapter 4. A compilation of the various flotation reagents, their trade names, manufacturers, and use has been prepared by H. T. Spedden. ANTIMONY The principal ore mineral of antimony, stibnite (Sb2 S3), is generally found in the U. S. in ore bodies in association with other valuable minerals such as galena (Pbs), sphalerite (ZnS), chalcopyrite (CuFeS2), or tetrahedrite (3Cu2 S – Sb2 S3), The sulfo-salt minerals of antimony, such as tetrahedrite or pyrargyrite, are often associated with high silver values, so that the presence of antimony may indicate economic importance even though the actual antimony content is low. Antimony is also significant to the mineral economy because of its occurrence in some ores where lead, gold, and silver are the

Jan 1, 1962

By Howard Hughes

IN drilling for water and oil to reasonable depths through the generally soft yielding clay and sand formation of the Coastal Plain of Texas, . Louisiana, and Mississippi, the rotating method of drilling was adopted, principally on account of the easy and quick penetration, and the low cost of the drilling plant. In favorable ground, free of heavy gravel and rock strata, as much as 1,000 ft. has been drilled in less than 36 hr., although such performances were of course rare. Hydraulic rotary drilling, or, as it is now called, rotary drilling, was used in the above States as early as 1880. The plant consisted of an ordinary derrick, a 25-h.p. boiler, a small hoist, a steam pump, and a water swivel with hose attachment, and an ordinary flat diamond-pointed bit. The successful drilling in of a phenomenal oil well by this process on Spindletop, near Beaumont, Texas, on Jan. 10, 1901, and the ascertained impracticability of drilling subsequent wells in the same locality by other methods (owing principally to heavy quicksand under pressure from below), brought rotary drilling into great prominence, practically to the exclusion of any other process throughout the Coastal Plain, and later on elsewhere. The method, as its name implies, involves the rotation of a pipe by means of machinery placed on the derrick floor. A drill bit attached to the lower end cuts a clearance for the drill pipe, with much the same motion and effect as an auger. Water forced through the drill pipe by means of a pump, and escaping through the bit, removes the cuttings and returns to the surface outside the drill pipe. In this manner the hole is kept open, permitting the drill stem to rotate freely. The pressure of the column of muddy water holds up the walls of the hole until it has been cased. Practically all the wells of the Gulf coast region, numbering nearly 10,000, have been drilled with this system. During the last five years its use has been extended to many other States and countries.

Jan 3, 1915

By R. J. Wysor

MoRe than two years ago, in making efficiency tests on our hot-blast stoves, I was surprised to discover a marked difference in temperature as indicated by a pyrometer inserted near a stove on blast, and the regular recording instrument situated near the bustle pipe. A special hole was then provided at the junction of the hot-blast main and the bustle pipe, and portable pyrometers with bare fire ends were used, both at this point and in the stove necks. I had occasion to make a number of such tests on various stoves on the same, furnace, the difference in temperature as shown by the two pyrometers varying chiefly with the temperature of the blast, and the distance of the stove from the furnace. However, this difference was always great, often averaging above 100" F., for the entire period of a stove on blast. Later, experiments were made with similar results on another group of stoves. The pyrometers used were properly standardized and checked against each other before and after each test. However, there was still a slight doubt as to the accuracy of the results obtained, as subsequently explained. But I have obtained corroboration of the magnitude of heat losses from blast-furnace hot-blast mains from two independent sources. I have learned from H. A. Brassert, Superintendent of Blast Furnaces, South Works, Illinois Steel Co., that he has recently done some experimental work similar to my own, and found temperature drops of the same order of magnitude. Also, C.,R. Lyle, of the Armstrong Cork Co., has made some interesting theoretical calculations, based on the thermal conductivity of fire brick, for the particular conditions of several of our tests; and his theoretical interpolations, all facts being considered, check our actual observations fairly well. I understand that Mr. Lyle expects to publish the results of his investigations. Method of Conducting the Tests The location of the pyrometer fire ends is shown in Fig. I, a plan of Bethlehem Steel Co.'s "G" blast furnace, hot-blast stoves, and main. Bare fire ends were used at both positions "A" and "B," being inserted

Jan 1, 1916

By Richard Moldenke

In crowding the recent mass of work on the physics of cast-iron into the compass of a short review, I cannot do better than to follow the lines of Mr. W. R. Webster's suggestion, made at the Florida meeting of the Institute, March, 1895.' The classification of the properties of the metal, and the influences to which it is subjected during the various processes it undergoes, is quite complete; and as Mr. Webster gives it again in full in another paper at the present meeting, a simple reference to it now will be sufficient. I. Correspondence Between Chemical Composition, and Melting-Point, Fluidity, Shrinkage, Fracture,Chill, Micro-Structure, and Other Physical Properties. Melting-Point.—The melting-point of cast-iron had long been a subject of controversy among foundrymen. They knew that a hard iron melted faster than a soft one, but this effect was occasionally disputed, and the reasons given were unsatisfactory; but could not be well controverted. It was my good fortune to take the actual melting-temperatures of some 70 pig-irons and castings; the Le Chatelier pyrometer, suitably protected, being introduced into the interior, and the iron melted off in a specially-constructed cupola. The irons had been previously analyzed by taking the borings at the point of the intro-

Jan 1, 1905

By William A. Longacre

In a previous paper the author discussed the problem described by the title of this paper, outlining and reviewing the Gish-Rooney method, with comparison and brief analysis of the interpretation techniques of Roman2 and Tagg.3 Some aspects of the simple type of two-layer system were reviewed from various sources.4, 5, 6 The Two-layer Problem For the configuration shown in Fig. I, and for any electrode separation A, the SurfAce of earth p, DepthH i P2 Infinite depth Fig. i.—Two-Layer system. apparent resistivity is a function of the relative depth the overburden resistivity pl, and a factor K defined by the equation P2 + P1 where p, is the resistivity of the lower bed. Thus, by the known theory of electrical images, p = pi [1+ */(*-7)] where The Multilayer Problem As the number of isotropic, homogeneous, horizontal layers increases, the difficulties of interpretation multiply. The theory becomes much more involved, and in view of the state of our knowledge, the general problem is virtually impossible of exact solution. However, certain types of multilayer problems can be worked out in terms of two-layer theory. Humme1,7 Pirson,8 Tagg,3 Watson,9 and others have pointed out the possibility of building up approximations of multilayer resistivity curves with suitable combinations of two-layer curves. Many three-layer curves can be constructed in this way to a good degree of accuracy, and special types of four-layer curves can be approximated. It is very likely that as the number of layers increases, the method of combination will not give good approximations except in very special cases. In the analysis of actual field data, the author has found that many obviously multilayer curves can be solved partially with a good degree of accuracy, using the theory that thin adjacent beds may be considered as one layer or zone, and applying two-layer theory to the extremities of the field curve. Modified Tagg Method of Interpretation Tagg's second method, though superior to his first, necessitates a large number

Jan 1, 1946

By William A. Longacre

In a previous paper the author discussed the problem described by the title of this paper, outlining and reviewing the Gish-Rooney method, with comparison and brief analysis of the interpretation techniques of Roman2 and Tagg.3 Some aspects of the simple type of two-layer system were reviewed from various sources.4, 5, 6 The Two-layer Problem For the configuration shown in Fig. I, and for any electrode separation A, the SurfAce of earth p, DepthH i P2 Infinite depth Fig. i.—Two-Layer system. apparent resistivity is a function of the relative depth the overburden resistivity pl, and a factor K defined by the equation P2 + P1 where p, is the resistivity of the lower bed. Thus, by the known theory of electrical images, p = pi [1+ */(*-7)] where The Multilayer Problem As the number of isotropic, homogeneous, horizontal layers increases, the difficulties of interpretation multiply. The theory becomes much more involved, and in view of the state of our knowledge, the general problem is virtually impossible of exact solution. However, certain types of multilayer problems can be worked out in terms of two-layer theory. Humme1,7 Pirson,8 Tagg,3 Watson,9 and others have pointed out the possibility of building up approximations of multilayer resistivity curves with suitable combinations of two-layer curves. Many three-layer curves can be constructed in this way to a good degree of accuracy, and special types of four-layer curves can be approximated. It is very likely that as the number of layers increases, the method of combination will not give good approximations except in very special cases. In the analysis of actual field data, the author has found that many obviously multilayer curves can be solved partially with a good degree of accuracy, using the theory that thin adjacent beds may be considered as one layer or zone, and applying two-layer theory to the extremities of the field curve. Modified Tagg Method of Interpretation Tagg's second method, though superior to his first, necessitates a large number

Jan 1, 1946